1. A tachometer measures:
Athe total number of miles/kilometers on your car.
Boil pressure.
Cgasoline level.
Dengine revolutions per minute.

  1. What is the main purpose of the alternator?
Ato regulate the speed of the car
Bto keep the engine cool.
Cto maintain constant oil pressure.
Dto power the car’s electrical system.

Verified Answer :

The answer for the first question is : D )  engine revolutions per minute.

The answer for the second question is : D ) 
to power the car’s electrical system.

-Hope this helps.