If you carry a u. s penny (weighing 0.025 n) to the top of the empire state building (449m) how much work have you done to the penny?

Abearing is designed to a reduce friction b. support a load c. guide moving parts such as wheels, shafts and pivots d. all of the above

With the simplified model of the eye, what corrective lens (specified by focal length as measured in air) would be needed to enable a person underwater to focus an infinitely distant object? (be careful-the focal length of a lens underwater is not the same as in air! assume that the corrective lens has a refractive index of 1.62 and that the lens is used in eyeglasses, not goggles, so there is water on both sides of the lens. assume that the eyeglasses are 1.90

The ph is the a. independent variable b. the dependent variable c. control group