PLEASE HELP 50 POINTS + BRAINLIEST TO THE CORRECT ANSWER The data show the growth of two bean plants over several weeks using four different fertilizers. The experimental data would be more valid of which of the following variables was included in the experiment?

a. A fifth fertilizer was tested.

b. Only one plant was tested.

c. The plants were grown at variable temperatures.

d. A control without fertilizer was included for each plant.

(The data is in the image)

Which of the following is the source of energy for photosynthesis? a.) glucose b.) chlorophyll c.) carbon dioxide d.) sunlight

(select all the correct choose each statement that is scientific. - the opinions of randomly selected participants in a survey prove the idea that global temperatures are not increasing on earth. - the universe's average temperature and rate of expansion support the idea that it began as one super-dense and hot mass 13.8 billion years ago. - ocean tides are caused by the uneven gravitational pulls of the moon and sun on different parts of earth. - human life is more valuable than other forms of life on earth because humans are more intelligent than other organisms.

Tropical rain forests support more species per unit area than any other terrestrial ecosystem. what is one way rain forests are important to the health of the biosphere?