I need help, what is the answer for this?
I suck at math(≧▽≦).

Twenty-five percent of the customers entering a grocery store between 5 p. m. and 7 p. m. use an express checkout. consider five randomly selected customers, and let x denote the number among the five who use the express checkout.

Elena is paid a constant rate for each hour she works. the table shows the amounts of money that elena earned for various amounts of time that she worked.

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.