Practice section 3-2
1. which of the following statements is true about prokaryotic cells?
a) all prokaryotic cells grow and reproduce.
b) all prokaryotic cells have cell membranes and cytoplasm.
c) all prokaryotic cells lack a nucleus.
d) all of the above are true of prokaryotic cells.

the correct answer is b

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.