Nitrifying bacteria obtain their chemical energy from: a. the reduction of no3- to nh4+. b. the formation of nh4+ from n2 gas. c. the oxidation of nh4+ to n2.

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

Long term exposure to waves can cause sunburns and skin cancer.

Ronald wants to see if a new shower cleaner works better in removing soap than his old cleaner. he uses the new cleaner on one half of the shower tiles and his old cleaner on the other half. identify the independent and dependent variables in this experiment. enter your answer in the space provided.