1. A 16 foot ladder is leaning against a wall. If the top slips down the wall at a rate of 4 ft/s, how fast will the foot be moving away from the wall when the top is 11 feet above the ground?
The foot will be moving at ft/s.?
2. Oil spilled from a ruptured tanker spreads in a circle whose area increases at a constant rate of 5.5 mi2/hr. How rapidly is radius of the spill increasing when the area is 11 mi2?
3. A spherical snowball is melting in such a way that its diameter is decreasing at rate of 0.4 cm/min. At what rate is the volume of the snowball decreasing when the diameter is 9 cm. (Note the answer is a positive number).
4. Water is leaking out of an inverted conical tank at a rate of 0.0112 m3/min. At the same time water is being pumped into the tank at a constant rate. The tank has height 12 meters and the diameter at the top is 6 meters. If the water level is rising at a rate of 0.25 m/min when the height of the water is 1 meters, find the rate at which water is being pumped into the tank.