Please solve a and b.
A batch of 27 injection-molded parts contains 6 that have shrinkage.
a) Round your answers to four decimal places (e.g. 0.9876). If two parts are selected at random and without replacement, what is the probability that the second part selected has shrinkage?
b) If three parts are selected at random and without replacement, what is the probability that all three parts have shrinkage?