What do the arrows in a food chain represent? a) the number of consumers that make up a food webb) the speed at which phototrophs make organic matterc) how energy moves from organism to organismd) how producers carry out photosynthesis

it's anything that aren't producers and consumers.

explanation:

you've got to be clear on what "this" is

explanation:

on disadvantage of hydroelectric power is the cost. another disadvantage of using hydroelectric power is finding a water source powerful enough to harvest hydroelectric power.