19. The total load of an industrial plant is 4000 kW, and the load operates at a power factor of 0.85 lag. If an 800-hp synchronous motor with 93.5% rated efficiency and operating at unity power factor is added,
what is the new value of power factor, in percent?
A. 89.5%
B. 88.2%
C. 76.0%
D. 98.6%

Apinion having 30 involute teeth of 6,5 module rotates at 220 r/min and transmits 2 kw to a gear wheel having 70 teeth; the addendum on both wheels is 4 of the circular pitch and the angle of obliquity is 200. determine; 3.1 the lengths of the path of approach and the arc of approach 3.2 the normal force between the teeth at an instant when there is only one pair of teeth in contact