Let A and B be independent events on a sample space S. Respond to the tasks below.
a. (i) Prove that the events A and B are also independent.
b. (ii) Using part (i), derive an expression for P(A∪B) in terms of P(A) and P(B).
c. (iii) Using the result from part (ii), evaluate P(A∪B) and P(A∩B) when P(A)=0.4 and P(B)=0.5.