An equilateral triangle gutter is 27 ft long, 1 ft wide across the top, and 6 ft deep. If rainwater flowed into the gutter at 12 ft3/min. How fast is the rate of the increasing level of rainwater in the gutter when the rainwater is 9 inches deep?

Water pumped out of a cylindrical container at a rate of 8 cubic meters per second. If the radius of the container is 0.4 m. How fast is the height of the water dropping?

A trapezoidal trough 10 ft long, 4 ft wide at the top, 2 ft wide at the bottom, and 2 ft deep. If water flows in at 10 cu.ft. per min, find how fast the water surface is rising, when the water is 6 in deep.

A tank is leaking water at a rate of 1 L every 4 minutes. The tank's base measures 1 m by 90 cm and its height is 45 cm. If it took 21 hours and 36 minutes for the tank to empty, how far below the top of the tank was the original height of the water in the tank?