1. The problem statement, all variables and given/known data Uploaded 2. Relevant equations Uploaded 3. The attempt at a solution Well I believe it to be Binomial as the probabilities never change. So I used it to solve for the moment generating function, I do howvere want to know if what I have done is correct and also how I went from sigma((Pe^t)^y(n y)q^(n-y)) as the book did this?