One estimate for the number of protons in Betelgeuse is 2.16 • 10^58. The mass of one proton is about 1.67 • 10^-27 kg. What is the total mass of all the protons in Betelgeuse?

Aschool typically sells 500 yearbooks each year for 50 dollars each. the economic calls does a project and discovers that they can sell 100 more yearbooks for every $5 decrease in price. the revenue for yearbook sales is equal to the number of yearbooks sold times the price of the yearbook. let x represent the number of $5 decrease in price. if the expression that represents the revenue is written in the form r(x)=(500+ax)(50-bx). to maximize profit, what price should the school charge for the yearbooks? what is the possible maximum revenue? if the school attains the maximum revenue, how many yearbooks will they sell?

Angles r and s are complementary. the measure of angle r is 31 degrees. which equation can be used to find angle s?

8. kelly wants to buy a magazine that is $25. later the magazine was marked up an additional 20%. what is the new price?