An aircraft has 116 seats. The airline has found, from long experience, that on average 2.5% of people who have bought tickets for a flight do not arrive for that flight. The airline sells 120 tickets for a particular flight.

(a) Calculate, using a suitable approximation, the probability that more than 116 people arrive for the flight.

(b) Calculate also the probability that there are empty seats on the flight. (C)