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A water tank has the shape of an inverted circular cone (point down) with a base of radius 6 feet and a depth of 8 feet. Suppose that water is being pumped into the tank at a constant instantaneous rate of 4 cubic feet per minute.

Draw a picture of the conical tank, including a sketch of the water level at a oint in time when the tank is not yet full. Introduce variables that measure the radius of the water's surface and the water's depth in the tank, and label them on your figure

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Final answer:

A water tank in the shape of an inverted cone is being filled at a constant rate. We use variables 'r' for the radius of the water's surface and 'h' for the depth of the water, with the ratio of r to h equivalent to the permanent dimensions of the tank. Calculus may be required to find the specific water level over time.

Step-by-step explanation:

The student is asked to visualize and understand the geometry of a conical water tank being filled at a constant rate. To represent the situation, let's use 'r' to denote the radius of the water's surface at any given time, and 'h' to represent the depth of the water in the tank at that time. Then, sketch a figure of an inverted cone with these variables labeled as well as the constant dimensions given: a radius of the base of 6 feet and a depth of 8 feet.

We know that the side ratios of similar triangles are equal, so the ratio of the depth to the radius of the tank at any time (h/r) is equal to the ratio of the depth to the radius of the full tank (8/6). Therefore, we can express r in terms of h as r = (3/4)h. Given that water is being pumped into the tank at a rate of 4 cubic feet per minute, we can relate this rate to the changing volume of the water in the tank to eventually find out how the water level, in terms of h and r, changes over time.

It's important to note that an understanding of calculus or related rates would be beneficial to solve for the specific water height at various times given the inflow rate, as this involves a dynamic system where the volume of the cone changes with respect to time.

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