The noise produced by a ______ cooled machine is less as the rotor moves in a medium of smaller density.

A. worst, ventilation B. poor ventilation C. better ventilation D. none of the above

A. Tractive B. Portative C. Either of the above D. None of the above

A. Method of average losses B. Equivalent current method C. Equivalent torque method D. Equivalent power method E. All of the above

A. solid B. hollow C. perforated D. any ofthe above