in which situations is work being done?
a. hannah leans against her locker, but it doesn’t move.
b. andy’s car rolls down a hill with the engine off.
c. a wind turbine stands still on a sunny, windless day.
d. a balloon expands as it is heated by the sun.
e, james pedals a stationary exercise cycle that doesn’t move.

The fish shown above is a tarpon. it is a fast-swimming and powerful open-water fish. its closest relatives, oddly, are burrow-dwelling conger eels that stay on the bottom. both eels and tarpon developed from snake-like larvae that float in the plankton during the first stages of life. once they mature, tarpon and eels are not found near one another in the ocean. the tarpon and the eel illustrate all of the following except