A manufacturer has a recently produced a batch of 17 smart phones. Unknown to them, 6 of these phones are defective (the rest of the phones are acceptable). The manufacturer takes a random sample of 3 phones and evaluates them. (a) How many samples of size 3 are possible that have exactly 2 defective smart phones? (b) What is the probability that a random sample of 3 of these smart phones has exactly 2 defective phones? Round your answer to 4 places after the decimal point, if necessary.