# math

posted by
**sonjay**
.

A pitcher knows how to throw five different pitches. He threw four pitches before the last batter was called out.

a) assuming he threw each pitch at LEAST once, determine the number of possible arrangements of his pitches.

b) assuming that he can use any pitch an unlimited number of times, determine the number the number of possible arrangements of his pitches.

Stuck on this one :-(