How much gravity is done by a workman carrying a 8kg sheet plywood up a 3m ramp inclined at an angle of 20 degrees to the horizontal?

Three coins are flipped. what is the probability that there will be at least two tails?

Me because some of question i don’t understand

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.