$2.50 per 1/4 hour. Can someone explain how to solve this?

Is the product of seventeen negative numbers, positive or negative ?

Find the perimeter of the triangle with vertices  d(3, 4),  e(8, 7), and  f(5, 9). do not round before calculating the perimeter. after calculating the perimeter, round your answer to the nearest tenth.  

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