Which statement best describes the difference in how water and glucose can move across a plasma membrane?
a. water enters and leaves by osmosis and glucose enters and leaves by simple diffusion.
b. both water and glucose enter and leave by active transport.
c. water enters and leaves by osmosis, while glucose requires facilitated diffusion.

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.