Ineed to find the mid point of the equation but i am not sure what points i put into the equation, since i'm not given any coordinates

For which of the following counts would a binomial probability model not be reasonable? a)the number of people in a classroom born in januaryb) the number of people in a classroom with red hair c) the number of people admitted to a hospital in a day with a particular disease d) the number of heart beats in a one-minute perio.

Let x have probability generating function gx (s) and let un generating function u(s) of the sequence uo, u1, satisfies p(x > n). show that the (1- s)u(s) = 1 - gx(s), whenever the series defining these generating functions converge.

Rachel is baking a cake but does not know if she wants to make a round or a square cake which cake has a larger area a round 8 inch cake or a square 9 inch cake