Answer:
c
Explanation:
b and d are out, the variables are changed. a would be a repetition, not a replication. c uses the same method and variables with a different control group
Answer:
evaporation or water runoff that's my tips
rain or thunder storm
Answer:
it produces amino acids and proteins. It is also needed to make chlorophyll in plants, which is used in photosynthesis to make their food.