4. 3pts each In a region, there is a 0.95 probability chance that a randomly selected person of the population has brown eyes. Assume 13 people are randomly selected. a) Find the probability that exactly 9 of them have brown eyes. (Please translate the problem and show what you are entering into your calculator) b) Find the probability that 12 or more of them have brown eyes. (Please translate the problem and show what you are entering into your calculator)

Step 1 ：This problem is about binomial distribution. The binomial distribution model is used to find the probability of success of an event which has only two possible outcomes in a series of experiments. In this case, the probability of success (a person having brown eyes) is 0.95. The number of trials is 13 (the number of people randomly selected). We are asked to find the probability of exactly 9 successes and the probability of 12 or more successes.

Step 2 ：Let's denote the number of trials as \(n\), and the probability of success on an individual trial as \(p\). So, \(n = 13\) and \(p = 0.95\).

Step 3 ：First, we need to find the probability that exactly 9 of them have brown eyes. This can be calculated using the binomial distribution formula. The result is approximately \(0.0028\).

Step 4 ：Next, we need to find the probability that 12 or more of them have brown eyes. This can also be calculated using the binomial distribution formula. The result is approximately \(0.8646\).

Step 5 ：So, the final answers are \(\boxed{0.0028}\) and \(\boxed{0.8646}\).