Which of these descriptions involves an example of a nonrenewable resource? a. solar energy reaches earth's surface. b. soda cans are made from aluminum. c. winds form due to temperature differences. d. trees grow back after a forest fire.

c. establishing proper sleep hygiene

the answer is true when observing or determining population size, a direct observation is use, in which each organism is counted in a population or in an area. one benefit of this measure is that you get the exact population count but it will take a long time to  determine  the  size  of a  population.

i am sorry but i need more information and a picture.