What is the difference between energy conservation and energy sustainability

Up to what percentage of the world's flora consisted of cycads during the triassic period? 100% 75% 50% 20%

Which statement describes how favorable traits in a population relate to natural selection? they are the only traits that ever exist in the population. they build in the population over time. they are rarely passed on to offspring. they are found only in a few individuals within the population.

Explain what is meant by a river’s load, and describe how the load is carried.