9. Calculate the probability of a model ensemble that uses simple majority voting making an incorrect prediction in the following scenarios. (Hint: Understanding how to use the binomial distribution will be useful in answering this question.)

a. The ensemble contains 11 independent models, all of which have an error rate of 0.2.

b. The ensemble contains 11 independent models, all of which have an error rate of 0.49.

c. The ensemble contains 21 independent models, all of which have an error rate of 0.49.