External stimulus. The rain is something out of your control while you're waiting. Rain is not something you are doing nor is it a response to you waiting for the bus.
The answer is E; Self-interest study. This is due to the fact that the financier of the research, the beverage company, has vested interests in the research and will therefore be intuitively biased for the results to favour the sales of the beverage.
Answer:
The reactivity of acetic acid with various chemicals.
Answer: This told him that the allele for a green pod is dominant to the allele for yellow pods.
Explanation: Dominant traits will express themselves even if the allele for the other trait is there. If all of the offspring were green even though they carried the allele for a yellow pod, green must be dominant.