Which best represents the value of x

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.

Sally deposited money into a savings account paying 4% simple interest per year.the first year,she earned $75 in interest.how much interest will she earn during the following year?

Find the solution on the interval [0, 2pi)