The members of a film crew are at least 75 miles from their camp and must carry equipment back to camp before a storm arrives. The storm is scheduled to begin in 24 hours. They plan to travel as far as possible by truck and then walk the rest of the way. The truck can travel at a rate of 10 miles per hour through the terrain, and the team can travel 2 miles per hour on foot. Which system represents the number of hours the crew can travel by truck, x, and on foot, y, to reach camp before the storm? x + y < 24 2x + 10y ≥ 75 x + y > 24 2x + 10y ≥ 75 x + y < 24 10x + 2y ≥ 75 x + y > 24 10x + 2y ≥ 75

If p(x) is the total value of the production when there are x workers in a plant, then the average productivity of the workforce at the plant is a(x) = p(x) x . (a) find a'(x). a'(x) = xp'(x) − p(x) x a'(x) = xp'(x) − p(x) x2 a'(x) = p'(x) − p(x) x a'(x) = xp'(x) − p'(x) x2 a'(x) = p'(x) − xp(x) x2 why does the company want to hire more workers if a'(x) > 0? a'(x) > 0 ⇒ a(x) is ; that is, the average productivity as the size of the workforce increases. (b) if p'(x) is greater than the average productivity, which of the following must be true? p'(x) − xp(x) > 0 p'(x) − xp(x) < 0 xp'(x) − p'(x) > 0 xp'(x) − p(x) < 0 xp'(x) − p(x) > 0