Do all living things require carbon ?

People who exercise for an hour may have lower cholesterol levels. is that a statement? a law? or a hypothesis?

Which muscle is responsible for inhalation ?

The fruit of a certain plant is sweet and fleshy. the seeds of this plant have a seed coat that is fairly tough. the seeds germinate better if they are exposed to acid, or scarification. what is the most likely type of dispersal for this seed? water animal wind