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Conference terri::cars_uk

Title:Cars in the UK
Notice:Please read new conference charter 1.70
Moderator:COMICS::SHELLEYELD
Created:Sun Mar 06 1994
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:2584
Total number of notes:63384

721.0. "MOT 'points' of interest." by SUBURB::FRENCHS (Gentry to the ratholer.) Mon Aug 14 1989 16:41

    My Landy is due its first (for me) MOT in October. 
    
    Could some one put here all the points of an MOT test, and at what
    point each test would fail.
                              
    Much obliged of DECpark.
    Simon
T.RTitleUserPersonal
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721.7YesIOSG::MARSHALLTue Mar 27 1990 17:4713
Yes they do, but there's a wide range that's acceptable.

I assume the 23 has circular bowls with the lamp held in a two-part
shell, this being fixed to the bowl with a spring on the lower right and two
adjusting screws on the top and left (invert left/right as necessary), this in
turn being covered by a shiny chrome rim fixed with one screw underneath?
(IE the standard lamp all kit cars have :-)
Turn the screws so that the main beam (not dipped) is 6 inches below the level
of the lights (sorry, forgot your lights are only five inches off the ground...)
and directly in front of them, when reflected off a wall fifteen feet in front
of the car.  That should satisfy the MOT, unless you get a tester on a bad day.

Scott.
721.8Anyone know any more?IOSG::MITCHELLElaineFri Jun 29 1990 18:044
    
    I hear that exhaust emmission tests are to be included in th MOT test 
     as from next year - anyone know any details?
    
721.9What the BBC news saidIOSG::MARSHALLHarry PalmerFri Jun 29 1990 18:4115
The Nine o'clock news said that as from next year, exhaust emission testing
will be part of the MOT.  Cars with more then 4% [may have been 4.5%] "carbon"
in the exhaust will fail.

Note the news only said carbon, and didn't mention CO2, CO or any other gas.

Some HGVs and other diesel vehicles will be exempt, but I don't think old
cars will be.  The justification is that virtually all cars could be very
cheaply "tuned" to comply with the regs, and that they would then run more
efficiently so saving the owner money in the long run.

Apparently most cars only emit 0.6% "carbon" anyway, so it shouldn't affect
many people.

Scott
721.10Radio 4 was different againSYSTEM::MOORHOUSEFri Jun 29 1990 19:0511
    On radio 4 I heard two reports say that carbon dioxide emissions would
    be checked then the third report said (without explaining the change)
    that carbon monoxide would be.
    I think it is sad that the level of scientific understanding of the
    people who prepare these reports is so low - I still don't know what
    the truth is, or even whether it's a measure intended to monitor green
    house gases, engine efficiency, poisonous emissions or what. Clearly,
    neither do they, if they don't know the difference between CO2 and CO.
    
    - Abi.
     
721.11NEARLY::GOODENOUGHFri Jun 29 1990 19:346
    > Note the news only said carbon, and didn't mention CO2, CO or any
    > other gas.
    
    Well, the carbon is the bad bit.  The oxygen component is beneficial.
    
    Jeff :-)
721.13BOOKIE::DAVEYFri Jun 29 1990 21:1516
Here in the US (or at least the parts of the US that have emissions teating)
the test is for carbon monoxide (CO) and unburned hydrocarbons (HCs).
Now some people got sneaky when they realised this was the case, throwing 
things like alcohol into the tank to temporarily reduce CO emissions, as 
alcohol burns cleaner than petrol. However, though cutting down on CO, the 
(temporarily) cleaner burn means that the alcohol gives off more CO2 than 
would be the case with plain old petrol. The testers got wise to this, so 
they instituted a CO2 check too, to catch the 'cheats'.
 
I know that the reason here in the US that diesel engines were exempted from 
emissions testing was primarily a strong trucking lobby. Is this the case with
the UK too? Will badly-tuned diesels continue to belch out black smoke
and all the carcinogens that go with it, or will these eventually come under 
the ruling too?

John
721.14don't believe everything that you readBONNET::HARDYTue Jul 03 1990 17:1912
    I seem to remember seeing (or hearing) somewhere, that some exhaust gas
    analysers measure one gas (eg CO2) but are graduated according to
    another (eg CO). Apparently it's cheaper to make these and the
    resultant indications are reasonably accurate.
    
    If this is the case, then maybee the wording of the law is going to be
    rather difficult to formulate and will no doubt make some money for
    solicitors.
    
    Does anyone know what I'm talking about, because I don't? 
    
    Peter 
721.15JANUS::BARKERJeremy Barker - T&N/CBN Diag. Eng. - Reading, UKWed Jul 04 1990 16:195
Re: .8

Anything which has a catalytic converter will also be exempt from this test.

jb
721.16Why?IOSG::MARSHALLHarry PalmerWed Jul 04 1990 18:074
Just because a car has a cat, doesn't mean its emissions are low; the cat could
be worn out, or poisoned, etc.

Scott
721.17Is a white cat better?IOSG::MITCHELLElaineWed Jul 04 1990 20:307
    
>>Just because a car has a cat, doesn't mean its emissions are low; the cat could
>>be worn out, or poisoned, etc.
    
  If I borrow next-doors Ginger Tom - where should I install it for my
    Landy's next MOT? :-)  (or should this be in the stupid questions note?)
                 
721.18OVAL::MACMILLANRSo many roads, so little timeWed Jul 04 1990 20:404
    So it's true.  Garfields realy are a valuable and essential accessory
    for the concerned motorist  ;-)
    
    Rob
721.19The mind boggles......SHAPES::STREATFIELDCVW Beetle.. IOSG::AIR_COOLEDThu Jul 05 1990 17:164
    Come here nice kitty....
    
    How d'ya fancy 10 mins. being locked inthe engine compartment of my Beetle
    little cat!                   ??
721.20Diesel emissionsBRIANH::NAYLORLUCAS, the inventors of darkness.Fri Jul 06 1990 14:074
The black fumes from diesels are being legislated against by the EC - sometime
in the next few years I think.  

If your car is belching carbon, something's wrong!
721.21MARVIN::RUSLINGMicroServer Phase V Session ControlMon Jul 09 1990 14:3012
What I read (yesterday in the Independent) was that they will test to make sure
that emissions of CO2 are not over 4.5%.  This should be easy for ordinary
well tuned cars.  Cats are excluded (good job, my three have got terrible
breath problems).  There are some weasle words about cars of a special nature
being allowed for at the tester's discretion.  I guess that this will allow
older cars to get by, even when failing the test.  So, Derek, all you'll have
to do is to find a tester with discretion...

Dave

PS I glanced at the last rolling road printout and the Marlin would pass, even
before I put (more efficient) electronic ignition on it.
721.22DIY analysisUKCSSE::RDAVIESLive long and prosperFri Aug 03 1990 18:428
    FYI, A garage in Thatcham has just installed a 'green machine'. This
    machine has a pipe you shove up your exhaust, and a set of 3 lights,
    red amber green (obvious really init?). Suppose to be set up to the new
    standard of emmisions, so you can do-it-yourself, test your car!.
    
    (It's the Q8 one on the A4 I think)
    
    Richard
721.23NEARLY::GOODENOUGHFri Aug 03 1990 19:045
    > (It's the Q8 one on the A4 I think)
    
    Hmm.  I bet they're worried then.
    
    Jeff.
721.24Hows the car breath test going to be implemented?NSDC::SIMPSONFile Under 'Common Knowledge'Fri Aug 03 1990 19:0914
721.25Included in MOTIOSG::MARSHALLHarry PalmerFri Aug 03 1990 19:282
The emission test will be part of the ordinary MOT.  Whether they'll put the MOT
price up as a result I don't know...
721.26BRABAM::PHILPOTTCol I F 'Tsingtao Dhum' PhilpottMon Aug 06 1990 14:245
I had my car serviced (24,000 mile service) at Ralph Motors in Basingstoke 
last week and they did an emission test as part of the service (no extra
charge that I could see).

/. Ian .\
721.28The answers yet again...IOSG::MARSHALLWaterloo SunsetTue Nov 06 1990 17:288
Starts sometime in 1991
Applies to all age cars (even 1920s "classic cars", etc)
And all age engines

The Government say all cars should pass if "properly maintained and tuned".
Consumer group surveys disagree with this...

Scott
721.305000rpm = 3000 rpm if you like!VOGON::KAPPLERTue Nov 06 1990 19:1010
    Not strcitly related, but.......
    
    A long time ago, Road Rallying insisted on strict noise checks. They
    measured these whilst stationery at a fixed number of revs. (5000rpm
    was popular).
    
    A friend of mine set up a small service where he would recalibrate your
    electronic rev counter for you...............
    
    JK
721.31From "Top Gear", 15 Nov 1990IOSG::MARSHALLWaterloo SunsetFri Nov 16 1990 17:0118
The emission tests in the MOT come into effect in 1991.

The test is for Carbon Monoxide.  There must be less than 4.5% of it in the
exhaust gases.  Didn't say whether this is by mass or volume.

The limit has been set based on figures obtained for post-83 cars.  A home-tune
(note not the company Home-Tune specifically) mechanic said this was too high,
the average he has observed is about 2.5%.

My opinion is that it is higher to allow older cars to pass.

They showed some exhaust readings on the program.  A car without cat had about
2.x% CO; one with a cat had 0.x% CO.  But the cat-car had a lot more %CO2.

How long does CO stay in the atmosphere before reacting to make something less
poisonous?

Scott
721.32BRABAM::PHILPOTTCol I F 'Tsingtao Dhum' PhilpottMon Nov 19 1990 14:3210
No - CO emission is inversely proportional to CO2 emmission - reduce the CO from
4.5% to 2.5% and you'll increase the CO2 substantially.

Whilst CO is poisonouse CO2 is a "greenhouse gas" causing global warming.

The figure was chosen as a compromise between reducing poisoning of pedestrians 
and poisoning of the planet.

/. Ian .\
721.33What affects CO readings - re modified enginesCHEST::RUTTERRutter the NutterMon Nov 19 1990 16:0815
721.34BRABAM::PHILPOTTCol I F 'Tsingtao Dhum' PhilpottMon Nov 19 1990 16:104
In any event I'm told that the tests will be performed with the engine at idle.

/. Ian .\
721.35Who defines 'idle' speed ?CHEST::RUTTERRutter the NutterMon Nov 19 1990 16:145
721.36CO becomes CO2 in the environmentJANUS::BARKERJeremy Barker - T&N/CBN Diag. Eng. - Reading, UKMon Nov 19 1990 16:218
Re: .32

> Whilst CO is poisonouse CO2 is a "greenhouse gas" causing global warming.

CO is oxidized to CO2.  CO is, like many substances, a so-called
"greenhouse gas", just to a different degree than CO2. 

jb
721.37But how long does it takeIOSG::MARSHALLWaterloo SunsetMon Nov 19 1990 16:546
Yes I know 2CO + O2 -> 2CO2 in the atmosphere, but how long does it take?

Are there any other natural processes that remove CO from the atmosphere?
(eg like SO2 dissolving in rain ;-)

Scott
721.38No time at all!WTHRDS::TOWERSAh, but I was so much older then; I'm younger than that nowMon Nov 19 1990 19:427
    >Yes I know 2CO + O2 -> 2CO2 in the atmosphere, but how long does it take?
    
    It is virtually instantaneous. That is why it is highly poisonous - it
    literally sucks the oxygen out of the air, or out of the haemoglobin in
    your blood if it gets that far.
    
    Brian
721.39CO and bloodIOSG::MARSHALLWaterloo SunsetMon Nov 19 1990 19:4918
Haemoglobin is an oxygen carrier.  It carries oxygen from the lungs to the bits
of the body that need it.  A haemoglobin molecule carrying an oxygen one is
called oxy-haemoglobin.

Due to the shape of CO molecules, they can also be carried by haemoglobin.
A haemoglobin molecule carrying CO is called carboxy-haemoglobin.

If there is CO in the air you breathe, carboxy-haemoglobin will form as well as
(in preference to?) oxy-haemoglobin, reducing the oxygen-carrying ability of
the blood, hence starving the body of oxygen.  This is why CO is poisonous, not
because it "sucks" the oxygen out of the blood...

I dispute the reaction being instantaneous.  If it is, then exhaust emissions
would contain no CO, as it would all have reacted by the time it reached the end
of the pipe.  Also, if it instantaneously reacts to CO2, why is everyone worried
about the level of CO increasing due to "pollution" from cars?

Scott
721.40PRFECT::PALKAMon Nov 19 1990 20:4522
    CO is poisonous because it forms a stable compound with Haemoglobin.
    
    Normally Haemoglobin can form an unstable compound with either O2 ro
    CO2, depending which is more plentiful. Thus in your lungs there is
    more O2 than CO2; the CO2 is released and replaced by O2. As it goes
    through your body the O2 is replaced by CO2.
    
    When the haemoglobin forms a compound with CO it is much more stable,
    and so you lose use of the haemoglobin, resulting in lower efficiency
    of your circulation. Eventually your body will build up an excess of
    CO2 and a deficiency of O2 - you suffocate.
    
    I dont know if the CO will eventually leave the haemoglobin, or if it
    can only be replaced by new haemoglobin as your body manufactures it.
    
    I would expect CO to eventaully react to produce CO2, as this is an
    exothermic reaction, however I have no idea how quickly it will proceed
    at normal atmospheric temperatures and pressure. It probably requires
    some intermediate molecules such as O3 or some of the components of
    acid rain (SO3 or NO3).
    
    Andrew
721.418-)SUBURB::SCREENERRobert Screene, UK Finance EUCMon Nov 19 1990 21:092
    I can just imagine the commend of the last few replies, squeezed onto
    the bottom of an MOT faliure's comment box!
721.42CHEFS::CLEMENTSDPublic Sector and TelecommsTue Nov 20 1990 11:3714
    Sorry, .38, but I think you are a mite off beam, there. From my days as a
    zoology student I recall that the danger in CO and haemoglobin is that
    the CO binds with the chelate part of the Haemoglobin molecule (the Fe
    atom in the middle of the molecule) and stops the Heamoglobin/Oxygen
    association process, thus preventing oxygen transport. 
    
    Also doesn't the energy requirement of the 2CO+O2-->CO2 reaction mean that
    far from being instantaneous, it needs a fair amount of energy putting
    in to make it proceed in a rightwards direction? If it were
    instantaneous you could get rid of the CO in a cars exhaust just by
    bleeding/pumping air into the exhaust pipe. You'd only then have to
    deal with the unburned hydrocarbons and Nitrogen oxides then.
    
    But then again, my memory could be fading....... ;^)
721.43JANUS::BARKERJeremy Barker - T&N/CBN Diag. Eng. - Reading, UKTue Nov 20 1990 18:099
The 2 CO + 02 -> 2 CO2 is the main reaction catalysed by a catalytic converter.
I don't know the Activation Energy for the reaction, but it is exothermic -
catalytic converters get very hot when operating.

Like many reactions it can occur at normal temperature/pressure without a
catalyst, but at a very slow rate.  The energy to make the reaction happen
comes from things like light.

jb
721.44MOT Exhaust emissions test figures.MCGRUE::FRENCHSSemper in excernereWed Mar 20 1991 16:1914
As of the 1st of November this year (1991) the following exhaust emission tests
will be part of the MOT test:

Manufacture	Exhaust
date		Tests
--------------------------------------------------------------------------
Pre 1975	Visible test for smoke etc.
75 - Jul. 83 	CO Not more than 6.0%, Hydro-Carbons not more than 1200 ppm
Post Aug. 83	CO not more than 4.5%, Hydro-carbons not more than 1200 ppm

This detail has come from a friend of mine who is a (the) Snr vehicle inspector
for the MOT in Manchester.

Simon.
721.45Will 'tuning goodies' make things better or worse ?CHEST::RUTTERRut-The-NutWed Mar 20 1991 17:278
721.46JUNO::WOODAwaiting new management.Wed Mar 20 1991 19:3414
re. .45

 Well, as most cars with all those items on will have been set up properly, it
would probably be improved, but in the contxt that you meant .....

 Well, as I understand it, high compression ratios are supposed to give a fuller
burn, so that I would have thought would improve it. And everything else, except
the cam is suppoed to aid efficiency, so again should improve it.

 Although I have no definite idea about all of this.


		 Alan
		~~~~~~
721.48Emission figures look OKNSDC::SIMPSONThe Clot Thickens...Thu Mar 21 1991 14:1316
RE: the exhaust gas figures for the MOT. They should be very easy to pass - it
should only single out the very badly maintained cars.

In Switzerland the CO figure is 1.5% +/- 0.5%. THE HC PPM is 3000 - rather more
liberal than the UK. When I was in the UK a couple of weeks ago, a garage was
very interested to know what the Swiss limits were (as the Uk ones weren't
available). He reckoned that if the 1.5% figure was introduced in the UK then
only 25% of cars would pass.

FYI, my VW Transporter had the following figures at its last test:

CO 1.71%, HC PPM 1172. CO2 12.3% (in Switzerland it must be greater than 12%).

Cheers

Steve
721.49Someone explain pleaseGRANPA::63654::NAYLORPurring again.Fri Mar 22 1991 22:337
Re -2 (idle speed versus 4000 rpm)

In Maryland, the emissions testing is done at 3000 rpm, off-load.  I must be
brain-dead (it is Friday afternoon after a l-o-n-g week!) but can't think of why
it makes a difference.

	Brian
721.50At least it was painless !FUTURS::LEECHO.K. Mr. Moley...Tue Jan 21 1992 20:0019
    
    Having just survived then annual M.O.T. (the car that is), I was
    interested at what the new Emissions limits were, and what the norm is.
    
    All I did find out was that Hydro Carbon Particles Per Million are
    normally around 200-300 level but can got up to 5,500 !!!
    
    I got an emission report with the M.O.T. Certificate which showed the
    following :-
    
    
    CO		 1.74%
    CO2		11.2 %
    HC		61   PPM
    O2		 4.60%
    AFR		17.2
    LAMBDA	 1.168
    
    Shaun.
721.51Cracked mirror - MOTIOSG::MERCHANTThu Mar 19 1992 15:254
    Anyone know if a cracked door mirror would be grounds for failure?  I
    can't replace mine pending insurance claim.
    
    Mike
721.52FUTURS::LEECHThree wheels on my wagon...Thu Mar 19 1992 18:437
>>    Anyone know if a cracked door mirror would be grounds for failure? 
    
    No.  The only mirror required for the MOT is the rear view mirror (or
    should the be the shaving mirror ? ;^)
    
    
    Shaun.
721.53On supplementary driving light inoperativeSUBURB::TAFF::WobRobert Screene, UK Finance EUCThu Jun 11 1992 20:5319
My Golf has four lights at the front.  The central two lights are 
driving lights, supplenting the main beam from the outer 
lights.  The main beam still works as on Golfs with two front 
lights.  

However one of the central driving lights does not.  Will I fail 
an MOT next week because of this?

I can always remove the fuse for the driving lights, so that both 
lights are inoperative during the test.

I have checked the earth, +12v feed, and replaced the bulb, which 
I have tested in the other side!  I really can't fathom why it's 
not playing the game.   Also the 3 lights are running at 100W each 
on main beam, so it's not lacking for limunance down a dark road 
at night.

thanks,
Robert.
721.54get it sortedBLKPUD::WILLIAMSHThu Jun 11 1992 21:539
    YES, it'll fail,
    
    it's a case of "all fitted lights must be operative"
    
    When I used to have a cheapo motorbike with dodgy indicators, if they
    were fitted then it would fail. take them off (which is Ok for a
    motorbike as you've still got your arms) and it would pass.
    
    Huw
721.55KERNEL::SHELLEYRI only _work_ in outer spaceFri Jun 12 1992 13:3210
721.56CARLIE::MITCHELLEBeware of the green meanieFri Jun 12 1992 14:332
    
    I thought .54 was correct, and that all fitted lights should work....
721.57KERNEL::SHELLEYRI only _work_ in outer spaceFri Jun 12 1992 15:146
    Re .56
    
    If you look at the MoT checklist I think it lists the lights that 
    need checking rather than a catch all "all lights must work" box.
    
    Roy
721.58FUTURS::TPEC02::markMilky, milky. LovelyFri Jun 12 1992 16:151
YEs. If it's there, it must work
721.59KERNEL::SHELLEYRI only _work_ in outer spaceFri Jun 12 1992 16:406
    Sorry, still disagree. Only things like sidelights, dipped/main beam
    are checked.
    
    I'll dig out my check list tonight. Why not do the same.
    
    Roy
721.60Lights etc...RDGENG::MOAKESRYour Robot sounds just like Pink Floyd.....Fri Jun 12 1992 17:149

I thought it was necessary to have legal requirement lights functioning ie 
Indicators etc..  and any accessory/factory extra lights such as front fogs or 
driving lamps can be non-functional if the examiner is told about it beforehand 
and the fuse/switch is disconnected.


_Richard (Who got though MOT with front fogs not working by telling examiner)
721.61Now I'm confusedNEWOA::ORCHARD_TAnd the next contestant, pleaseFri Jun 12 1992 17:222
    Motorcycles don't fail if the 'parking light' doesn't work - even if
    it's just a blown bulb (i.e. it should work)
721.62I've been taught this by thems that know...BASCAS::BELL_A1two wheels and 138bhp....Fri Jun 12 1992 18:4818
721.63HmmmmNEWOA::ORCHARD_TAnd the next contestant, pleaseFri Jun 12 1992 20:529
    Alan,
    
    Well, last time I MOT'd a bike (Honda 250, last year), the tester
    commented on the two bikes in front of me as not having a working
    parking light, and it not being a fail (mine worked though :-))
    
    So, one of us is wrong (and I don't really care which ;-)
    
    Tony (the wimp) Orchard
721.64FORTY2::NAYLERMike NaylerMon Jun 15 1992 13:5712

Well my car recently when through its MOT, it did fail however the number plate 
light not working did not cause the failure.  The MOT chap adviced me to get it 
fixed, however he also said that I would not fail the MOT if I did not fix it.
Needless to say I did fin the light and all the other stuff.





Mike
721.65KERNEL::SHELLEYRKnocking on Heaven's daw-wawMon Jun 15 1992 21:5920
    On the MOT Inspection Report it lists the following -

    Lighting Equipment

    Front & rear lamps
    Headlamps
    Headlamp aim
    Stop lamps
    Rear reflectors
    Diection indicators

    Now I guess you could argue that "Front & rear lamps" would cover all
    lights but I believe it just refers to side lights.

    Whilst I certainly advocate that all fitted lights _should_ be in
    working order, auxillary lights (whether factory fitted or not)
    including fog lights, and rear number plate light (as mentioned in
    previous note) do not need to be working in order to pass the MoT.

    Roy
721.66LARVAE::DRSD21::PATTISON_MI will tell you this boy...Mon Sep 14 1992 14:034
    Will My car fail with a small crack, about half an inch, which is 4-5
    inches below the eye level in the windscreen ?
    
    M:
721.67JANUS::BARKERJeremy Barker - CBN - Reading, UKMon Sep 14 1992 17:178
Re: .66

At present, no.

From January it will fail if there is a crack or bad chip in the
driver's field of view (how this is defined I don't know).

jb
721.68Soft tops ?FORTY2::HOWARDIt'll always be Pompey Poly !!Mon Sep 14 1992 18:265
    What about soft tops where the plastic that is substituted for the rear
    screen and the quarter windows has "gone a bit cloudy" ??
    
    Barry
    
721.69MARVIN::RUSLINGDave Rusling REO2 G/E9 830-4380Mon Sep 14 1992 20:086
	I've never tried this, but I've heard that cleaning them with 
	toothpaste does a real good job with these.  I've no idea about
	the MOT...

	Dave
721.70You jeast perhaps !!FORTY2::HOWARDIt'll always be Pompey Poly !!Mon Sep 14 1992 20:304
    Toothpaste.....WHAT !!
    
    Barry
    
721.71MARVIN::RUSLINGDave Rusling REO2 G/E9 830-4380Mon Sep 14 1992 21:554
	I'm only reporting what I heard (from a vintage car owner)...

	Dave
721.72PLAYER::BROWNLMaintain the rigidityTue Sep 15 1992 12:198
    Toothpaste contains a very fine abrasive, which is why you shouldn't
    use too much of it. Brasso will perform the same function. Best of all,
    I'd suggest Autoglym's glass cleaner and polish.
    
    Mind you, it would take hours to deal with any big imperfections, and
    it can't fill a hole.
    
    Laurie.
721.73SAC::DRSD21::PATTISON_MI will tell you this boy...Tue Sep 15 1992 12:574
    I'm talking about a crack here, not a scratch, I don't see how any
    abrasive cleaner can repair a crack.
    
    M: