Why is coal considered a non renewable resource

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.

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.