Question on engine class in Mario Kart DS

I have been playing Mario Kart DS for the last several days and beginning to play in the 100cc and 150cc engine class races. I like to ask two questions on the classes:

a) What does "cc" mean?

b) Do the engine classes reflect the speed of the karts?

To answer your second question, the higher the engine class, the faster the karts go in the game.podliver

it also ups the difficulty of the comps