An ecologist studying communities would study which of the following? a. the development of males' mating dances in a particular species of spider. b. changes in the size of a mouse population after hawks, a main predator of mice, are introduced into the area where the mice live. c. changes in the abundance of a particular species of frog in a portion of a rainforest over time. d. the effects of soil erosion on plant species found on the side of a mountain

B. Changes in the size of a mouse population after hawks, a main predator of mice, are introduced into the area where the mice live

Explanation:

A community is defined as a group of populations of two or more different species which inhabit the same area at a certain time.

Community ecology is the study of the interactions between species in communities through time on a certain place. It includes the study of the distribution, structure, demography, and interactions between populations.

the core of the sun is so hot and there is so much pressure, nuclear fusion takes place, hydrogen is changed to helium. nuclear fusion creates heat and photons. when the heat reaches the earth it warms the molecules of the atmosphere, and they warm other molecules and so on.

answer: substrate concentration. enzymes work best when there is a high enough substrate concentration for the reaction they catalyse.