"Visible light is light that has wavelengths that can be detected by the human eye. The wavelength of visible light determines the color that the light appears. As you can see in the Figure below, light with the longest wavelength appears red, and light with the shortest wavelength appears violet."
Answer:
It would be the plant type
Explanation:
This is because you are measuring the growth of 2 different plants, so they can not be the same. all the other options ARE constants
The answer is the endogenous opiate.
The human body naturally produces its own opiates like substances and uses them as neurotransmitters. These substances include endorphins, enkephalins, and dynorphin, often collectively known as endogenous opioids. Endogenous opioids modulate our reactions to painful stimuli.