<span>The correct answer is B. their kidneys can't excrete concentrated salt. Since salt is dissolved in water, the organism sends its water reserves to the kidneys to dissolve and excrete the salt but this leads to dehydration. That's why people at sea who don't know what they're doing often dehydrate themselves by drinking sea water, thinking that they're safe.</span>
For the first question, I would say a line graph. And the one about the human heart, I need some more information.
<span>C. generate a topic
Examining different writings could help you produce ideas.
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Doppler effect and redshift as the light coming from stars from the distance can be shifted in the same way as a pitch of sound does
I believe the answer is an eclipse.