Human activities
a. exacerbate the natural greenhouse effect
b. create the greenhouse effect
c. diminish the greenhouse effect
d. eliminate the greenhouse effect

B

Human activities will only make the greenhouse effect worse. The more we make in factories, the more smoke comes out of chimneys. The more smoke goes in contact with ozone, the more ozone is made.

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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.