Customers arrive at a bank according to a Poisson process with a rate of ???? = 2 customers for a five-minute period. Find the probability that

(i) three customers will enter the bank between 2:00 p.m. and 2:15 p.m.;

(ii) three customers will enter the bank between 2:00 p.m. and 2:15 p.m. and two customers will enter the bank between 2.15 p.m. and 2:30 p.m.;

(iii) three customers will enter the bank between 2:00 p.m. and 2:15 p.m. and at most two customers will enter the bank between 2:15 p.m. and 2:30 p.m.