_28_ (20 sobre menos7) _-81__ -7 -9
(Menos81
sobre menos9)

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.

Pls the last one and it has to be like number 6

240 seventh graders and two-thirds of the students participate in after-school activities how many students participate in after-school activities