1. A rectangular piece of cardboard measuring 26 inches by 42 inches is to be made into a box with an open top by cutting equal size squares from each comer and folding up the sides.

Let x represent the length of a side of each such square. What is the maximum volume of this box? If necessary, round to 2 decimal places.

2. A coin is tossed upward from a balcony 220 ft high with an initial velocity of 48 ft/sec. During what interval of time will the coin be at a height of at least 60 ft?

(h = -16t2 + v₀t + hQ)