Prior, Conditional and Posterior Probability

"A consulting firm submitted a bid for a large research project. The firm’s management initially felt they had a 50/50 chance of getting the project. However, the agency to which the bid was submitted subsequently requested additional information on the bid. Past experience indicates that for 75% of the successful bids than 40 % of the unsuccessful bids the agency requested additional information.
a. What is the prior probability of the bid being successful (that is , prior to the  request for additional information)?
b. What is the conditional probability of  a request for additional information given that the bid will ultimately be successful.
c. Compute the posterior probability that the bid will be successful given a request for additional information.
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