What must be true in order for P(A OR B)=P(A) +P(B)?

Question

a and b cannot be disjoint
a and b must be independent
a and b cannot be independent
a and b must be disjoint
it is always true

2. What must be true for P(A and B)=p(A) * P(B)

a and b cannot be independent
a and b must be disjoint
a and b cannot be independent

Answer 1

1. must be disjoint

Answer 2

1. A and B must be disjoint

2. A and B must be independent

2/2 correct 100%