Suppose that in the population of twins, males (M) and females (F) are equally likely to...

Suppose that in the population of twins, males (M) and females (F) are equally likely to occur and that the probability that twins are identical is α. If twins are not identical, their genes are independent.

a. Show that

b. Suppose that n twins are sampled. It is found that n₁ are MM, n₂ are FF, and n3 are MF, but it is not known which twins are identical. Find the mle of α and its variance.