An open drainage canal is to be constructed to carry water at a maximum rate of 106 gpm. The canal is concrete-lined and has a rectangular cross section with a width that is twice its depth. The...

An open drainage canal is to be constructed to carry water at a maximum rate of 106 gpm. The canal is concrete-lined and has a rectangular cross section with a width that is twice its depth. The elevation of the canal drops 3 ft per mile of length. What should the dimensions of the canal be?