Hardy-weinberg equilibrium assumes: a. gene flow that is equal both into and out of the population. b. no gene flow, mutation, or natural selection. c. strong selection pressure on the trait(s) being studied. d. a significant mutation rate from generation to generation.

b. no gene flow, mutation, or natural selection.

Explanation:

A population can attain Hardy-Weinberg equilibrium only under certain conditions. The population should have a large size so that any chance events such as genetic drift do not affect the allele frequency. Likewise, the population should not be experiencing any operative evolutionary forces. This means that there should not be immigration or emigration of organisms and no gene flow. The population should also not experience mutation and natural selection so that the allele frequencies remain constant over the generations.

b. lithosphere, asthenosphere, mesosphere   is the answer most likely

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.