The independent is the amount of time you do sit-ups the dependant is your heart rate because it will speed up
the control is how much effort that you put out doing sit ups
Answer:
Solar Energy
Explanation:
The reasoning is most of the energy comes from the Sun to support ecosystems and help them grow, such as various plants.
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Answer:
Photons
Explanation:
Photons are the only source of energy for photosynthesis. Photons are absorbed by chlorophyll molecules within Photosystems I and II (and antennae complexes), generating higher-energy ‘excited’ states of the photosystems which can carry out energetically costly chemical reactions.
