50 pounds of a working substance undergoes a non-flow process. the internal energy at the start of the process is 89 btu/lbm and at the completion of the process is 150 btu/lbm. a total of 350 btu of work is done on the working substance. how much heat was added or removed from each pound of the working substance (btu/lbm)

An insurance company wants to know if the average speed at which men drive cars is higher than that of women drivers. the company took a random sample of 27 cars driven by men on a highway and found the mean speed to be 72 miles per hour with a standard deviation of 2.2 miles per hour. another sample of 18 cars driven by women on the same highway gave a mean speed of 68 miles per hour with a standard deviation of 2.5 miles per hour. assume that the speeds at which all men and all women drive cars on this highway are both approximately normally distributed with unknown and unequal population standard deviations.

Which sound characteristic is not affected by the relative motion of an object

Which type of energy would have nothing to do with ironing clothes? a. heat b. chemical c. electrical d. mechanical