A spherical sonar transducer with 15 in. diameter is to be towed in seawater. The transducer must be fully submerged at \(55 \mathrm{ft} / \mathrm{s}\). To avoid cavitation, the minimum pressure on the surface of the transducer must be greater than 5 psia. Calculate the hydrodynamic drag force acting on the transducer at the required towing speed. Estimate the minimum depth to which the transducer must be submerged to avoid cavitation.