C. because stimuli is how your body responds to something, and in this case, someone's heart rate increases WHEN their blood oxygen drop. Do you see how it responds? ;-)
Q: this picnic table was made from fallen trees in a local forest. is this picnic table a biotic or abiotic factor? explain your answer.
A: the answer would be biotic because the term biotic means that something is living or had lived before. as you can see, the table was made by fallen trees in the local forest. that means it lived before the tree was fallen and carved into a picnic table.
hope this helps! ❤ from peachimin
Have a control. You have to have something to compare your experimental results or else your results could be random chance.
The answer you are looking for is C. Nitrogen. Commonly found as Nitrite
(N3) or Nitrate (N2) nitrogen is a key element required by all life. Nitrogen is most often released back into the atmosphere by micro-organisms during the decomposition of organic matter, and into the ground through decomposition and defecation (Pooping).