A firm buys components from two suppliers: 60 percent from supplier A and the rest from supplier B. It so happens that 9 percent
of the components from supplier A are defective and 15 percent of the components from supplier B are defective. (a) What is the probability that the next component the firm buys is defective? (b) What is the probability that the component that the firm buys is from supplier B if we know that it is defective?