**A conical tank (with vertex down) is 10 feet across the top and 12 feet deep. If the water is flowing into the tank at a rate of 10 cubic feet per minute, find the rate of change of the depth of the water when the water is 8 feet deep.**

**Answer:**

**A conical tank (with vertex down) is 10 feet across the top and 12 feet deep. If the water is flowing into the tank at a rate of 10 cubic feet per minute, find the rate of change of the depth of the water when the water is 8 feet deep.**

**Answer:**