A textile company starts in its first year with an output of 2,000 shirts and 1,000 trousers. The production of shirts increases by 500 shirts every year, and the number of trousers rises by 20 per cent every year.

(a) How many shirts and trousers are produced in the second, third and tenth years?

(b) What is the total output of shirts and trousers after 15 years? (Use given formulas.)