Or commercial fish farming, is one way in which new species enter freshwater and marine ecosystems.
a. aquaculture,
b. biodiversity,
c. conservation,
d. pollution,

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.

the dna of humans and mice is almost 92% similar. this similarity indicates that . mice have a tail, while humans have a tailbone. the tailbone is a structure in humans.yes it's true.