Two different types of injection-molding machines are used to form plastic parts. A part is considered defective if it has excessive shrinkage or is discolored. Two random samples, each of size 300, are selected, and 15 defective parts are found in sample from machine 1, and 8 defective parts are found in sample from machine 2. (a) Is there a reasonable to conclude that both machines produce the same fraction of defective parts, using = 0.01? Find P-value for this test. (b) Construct a 99% confidence interval on the difference in the two fraction defectives.