Two workers unload a 100 kg bed frame from a truck whose bed is 1.04 m above the ground. They carry it up 5 flights of stairs (each flight is 2.5 m tall) to Larry's apartment. When they get there, Larry tells them that
he never ordered a bed frame. After some confusion and heated words, the workers take the bed frame
back down the stairs and put it back on the truck.
Calculate the net work done by the workers on the bed in this process. Report you answer to the nearest kJ.

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.

Look at the potential energy diagram for a chemical reaction. which statement correctly describes the energy changes that occur in the forward reaction?

9.98 kg of r-134a at 300 kpa fills a rigid container whose volume is 14 l. determine the temperature and total enthalpy in the container. the container is now heated until the pressure is 600 kpa. determine the temperature and total enthalpy when the heating is completed. use data from the steam tables.