In which of the following situations is the most work done on the object?
a. holding a 50 kg object.
b. carrying a 30 kg object down a 40 m long hallway.
c. lifting a 20 kg object 1 m up.
d. carrying a 15 kg object up a flight of stairs.
e. lowering a 25 kg object from a second story balcony to the ground

What are igneous intrusions and extrusions

Acommercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -35°c by rejecting waste heat to cooling water that enters the condenser at 18°c at a rate of 0.25 kg/s and leaves at 26°c. the refrigerant enters the condenser at 1.2 mpa and 50°c. if the compressor consumes 3.3 kw of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigeration load, (c) the cop, and (d) the minimum power input to the compressor for the same refrigeration load.

The ability to make things happen is also called a. heat b. force c. matter d. energy