The first one is going to be b and the second one is going to be a
Answer:
Most humans cannot see ultraviolet light because it has a smaller wavelength than violet light, putting it outside of the visible spectrum.

Answer:
There is a chance that the person receiving that insulin will get a bad immune response, and there is a possibility that the animal might have a disease or infectious organisms, that their insulin might contain, and putting it inside a human might transmit that disease.
Explanation:
Yes there is, there is the cycle which trees and plant organisms produce oxygen, and homes animal organisms which can be beneficial to decomposition and other things.
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