Coral and algae that live in coral polyhs have a special relationship. each contributes something that the other needs to survive. this is an example of
a) mutualism (i think its this)
b)parasitism (probably not)
c) communication (obviously not)
d)commensalism (no)

i think it's they require warm air

explanation:

tornados usually happen when it's raining right so when it's raining it cools down so if the temperature keeps changing then i think a tornado occurs sorry if it's wrong

it creates acid rain

"do a testcross with a homozygous recessive plant."

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what do the different brain waves do?

explanation:

brainwaves are produced by synchronised electrical pulses from masses of neurons communicating with each other. brainwaves are detected using sensors placed on the scalp. brainwave speed is measured in hertz (cycles per second) and they are divided into bands delineating slow, moderate, and fast waves.