Can u show a pic of the question
Answer:
1. The retina contains three kinds of colour receptors
Explanation:
Young-Helmholtz theory color vision says human can perceive colour due to the presence of colour receptors in the retina that receives colour in various wavelengths
Answer: B is the answer.
Explanation: Disinfecting a surface is cleaning off dirt and germs. When you use soap and water to remove dirt, your disinfecting it the surface, meaning your cleaning off the germs so you and your family or peers don't get sick.
Let me know if you have any questions.
~ Lily, from Brainly.
True because they are like man made pain killers that your body produces
