Please help with this!

1. convert. simplify your answer and write it as a proper fraction or as a whole or as a mixed number.4oz =_ pounds2. what is 1/3 of 66for both show work.

Which of the following answers is 7/9 simplified? 7/9 2/9 11/9 2/7

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.