When Andrea needs a taxi, she rings one of three taxi companies, A, B or C. 50% of her calls are to taxi company A, 30% to B and 20% to C. A taxi from company A arrives late 4% of the time, a taxi from company B arrives late 6% of the time and a taxi from company C arrives late 17% of the time.

1. Find the probability that, when Andrea rings for a taxi, it arrives late.
2. Given that Andrea’s taxi arrives late, find the conditional probability that she rang company B.