Probability Question?

Intersection A is located downstream of intersection B. A traffic engineer observed that during the morning peak period the probability that intersection A is congested is 0.32. There is a 0.56 probability of A being congested given the knowledge that B is congested. On the other hand the probability of B being congested given the knowledge that A is congested is 0.88. Calculate the probability that (a) B is congested during the peak period and (b) at least one of the two intersections is congested.