A cotton cultivar, designated 02X38R, is disclosed. As a result, the rotation velocity of the motor may be correctly controlled. As the controlling current is substantially smaller than the load current, the power losses are negligible in comparison with a measuring shunt that is connected in series to the load. A difference can then be calculated between the student speech sample duration disparity and the reference speech sample duration disparity. The invention further relates to the process to make the composition and its use in greases.