Probability of two events

A company believes there is a 40% probability of winning the first contract. If they win the first contract, the probability of winning the second is 70%. However, if they lose the first contract, the president thinks that the probability of winning the second contract decreases to 50%.

a) What is the probability that they win both contracts?

b) What is the probability that they lose both?

c) what is the probability that they win only one contract?

a) do I add the two chances 70+40 then divide it by 200?

b) same as A but with the losing percentages?

c)

Can someone help me with these ? Thank you.