Say we have m bins and n balls. If we throw the balls in the bins at random ( they all have the same chance of getting a ball each time )

Let j be one of the bins.

a ) What is the probability that none of the balls land in bin j?

b ) What is the probability that exactly one ball lands in bin j?

c ) What is the probability that at least 2 balls land in bin j?

d) What is the expected number of bins to have 2 or more balls ?