A boy weighing 25 kg sits in a 1000 kg car at a speed of 15 m/s. What is the total momentum of the car and the boy?
A) 375 kg m/s
B) 14625 kg m/s
C) 15000 kg m/s
D) 15375 kg m/s

Liquid from a brewery fermentation contains 10% ethanol and 90% water. part of the fermentation product (50,000 kg/h) is pumped to a distillation column on the factory site. under current operating conditions, a distillate of 45% ethanol and 55% water is produced from the top of the column at a rate of one-tenth that of the feed. what is the composition of the waste "bottoms" from the still?