NEED HELP ASAP PLEASE SOLVE! Will give 15 points.

You are constructing a histogram for scores that range from 70 to 100 in whole points. frequencies range from 3 to 10; that is, every whole-point score between 60 and 100 occurs at least 3 times, and at least one score occurs 10 times. which of these would probably be the best range and size for the score intervals along the x-axis?

Suppose i flip two identical coins. what is the probability that i get one head and one tail?

Find the zero function by factoring (try to show work) h(x)=-x^2-6x-9