(The clepsydra, or water clock) A 12-h water clock is to be designed with the dimensions s...

(The clepsydra, or water clock) A 12-h water clock is to be designed with the dimensions shown in Fig, shaped like the surface obtained by revolving the curve y = f(x) around the y − axis. What should be this curve, and what should be the radius of the circular bottom hole, in order that the water level will fall at the constant rate of 4 inches per hour (in./h)?

FIGURE The clepsydra.