The number of memory chips M needed in a personal computer depends on how many application programs, A, the owner wants to run simultaneously. The number of chips M and the number of application programs A are described by M = 4 chips for 1 program, 4 chips for 2 programs, 6 chips for 3 programs, 8 chips for 4 programs, PA (a) = 0.1(5 − a) a = 1, 2, 3, 4, 0 otherwise. (2.90) (1) What is the expected number of programs µA = E[A]