Which of the following is equal to 7 to 1/4 power?

Alocal concert promoter purchases 2 3/4 pages of ads. when one of the concerts is cancelled, the promoter cancels 1 5/8 pages of ads. how much advertising space is the concert promoter actually using?

Express the following as a function of a single angle, cos(60) cos(-20) - sin(60) sin(-20)

Complex numbers multiply √-4 * √-25 and show all intermediate steps. alternative notation is sqrt(-4) * sqrt(-25).