Pls help me unit 6:exponents & exponential functions homework 4: negative exponents

Suppose that the price p (in dollars) and the weekly sales x (in thousands of units) of a certain commodity satisfy the demand equation 4p cubedplusx squaredequals38 comma 400. determine the rate at which sales are changing at a time when xequals80, pequals20, and the price is falling at the rate of $.20 per week.

Let x = a + bi and y = c + di and z = f + gi. which statements are true?

Acredit union pays 5% annual interest, compounded daily, on saving deposits. find the value after one year of $500 deposited in this account. a-$20.40 b-$25.64 c-$520.40 d-$525.64