A computer store helps models of a computer (m1,m2,m3,m4). Each model can be fitted with 3 sizes of hard drive...

A computer store helps models of a computer (m1,m2,m3,m4). Each model can be fitted with 3 sizes of hard drive (A,B and C) What are the sample space? What are the probability of choosing a computer with a size C hard drive at random? What are the probability of choosing a model 2 computer with a size A hard drive at random? Can you please help.