Under his cell phone plan, Cameron pays a flat cost of $41 per month and $5 per gigabyte. He wants to keep his bill under $65 per month. Write and solve an inequality which can be used to determine xx, the number of gigabytes Cameron can use while staying within his budget.

Really need on these. i have no idea what to do

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.

Find the value of the variable and the length of each secant segment.