When patients receive blood transfusions, it is critical that the blood type of the donor is compatible with the patients, or else an immune system response will be triggered. For example, a patient with Type O- blood can only receive Type O- blood, but a patient with Type O+ blood can receive either Type O+ or Type O-. Furthermore, if a blood donor and recipient are of the same ethnic background, the chance of an adverse reaction may be reduced. According to a 10 -year donor database, 0.37 of white, non-Hispanic donors are \(\mathrm{O}+\) and 0.08 are \(\mathrm{O}-\).

(a) Consider a random sample of 15 white, non-Hispanic donors. Calculate the expected value of individuals who could be a donor to a patient with Type O+ blood. With what standard deviation?

(b) What is the probability that 3 or more of the people in this sample could donate blood to a patient with Type O- blood?