I am not sure but I am guessing carbon and nitrogen :)
Answer;
-Simple squamous epithelium
Explanation;
-Simple squamous epithelium is the single layer of thin, flat cells that line body surfaces which are not exposed substantially abrasive forces. The primary function of the columnar cell is that secretion and absorption simple squamous epithelium a single layer flat scale shaped cells.
-Simple squamous epithelium lines the air sacs, or alveoli, of the lungs. The alveoli are sites where air is exchanged in the lungs. Simple squamous epithelial cells in the alveoli allow oxygen from the air to enter the blood in the capillaries of the lung.
Answer:
The activity factor was modified. Ambulating indicates that the person is active. Even small activities require energy. So, people who can walk around and aren’t bedridden expend more calories than people who need to be on bedrest all day. Also, when the stress factor was changed to severe infection, the caloric requirement increased. This increase is probably because the immune system requires more energy to fight off the infection
hope this helps
Answer:Option A
Explanation: The snail breaths in the O2 which will then exhale CO2, therefore the plant will take that and process the CO2 back into O2.