Hi I'm having trouble with this question:

Let A and B be independent events, where P(A) = 0 and P(B)=x

a) write down an expression for P(A ∩ B)

b) Given that P(A U B) = 0.8,

i)find x

ii) find P(A ∩ B)

c) Hence, explain why A and B are not mutually exclusive

Any help is greatly appreciated. =)