If AAA and BBB are independent, P(A)=0.3P(A)=0.3P(A)=0.3, and P(A∪B)=0.6P(A \cup B)=0.6P(A∪B)=0.6, what is P(B)P(B)P(B)?
3/7
4/7
1/2
0.3