company has three factories (1, 2, and 3) which produce the same chip. The threefactories produce 15%, 35% and respectively 50% of the total production. The probabilityof a defective chip at factory 1, 2, 3 is 0.01, 0.05, 0.02, respectively. Suppose someone findsa defective chip. What is the probability that this chip comes from factory 1