PLEASE HELP DUE TODAY

Find the condition that the zeros of the polynomial f(x) = x^3+3px^2+3px+r may be in a.p.

Mallory has been offers two different jobs. she can baby sit for 6 hours a week and get $8.50 an hour. or she can work at the library for 14 hours a week and make $5.50 an hour. which job will allow her to save the most money after 6weeks?

If she had a problem that was like this how would you solve it? 9/5 x (4x1/6)