Plants use photosynthesis to:
a. store chemical energy, and they use cellular respiration to harvest energy.
b. change light energy into sugars.
c. change light energy into chemical energy as well as to harvest chemical energy.
d. harvest energy, and they use cellular respiration to store chemical energy.

C. change light energy into chemical energy as well as to harvest chemical energy.

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.

explanation:

the sun shines white and black light to our planet. the white light has all the colors in it. in our upper atmosphere, we have dust particles and oxygen molecules. the white light meaning all of the colors in a rainbow shines through the upper levels of the atmopshere and the blue light scatters across the entire planet. that is why our sky is blue.