8. devices that absorb neutrons and are used to control the speed of a fission
reactor are called

a reactor vessels
b fuel rods
c control rods
d containment buildings

C. control rods

Explanation:

Devices that absorb neutrons and are used to control the speed of a fission reactor are called control rods. They are used in nuclear reactors to control the fission rate of uranium and plutonium. They are composed of chemical elements that are capable of absorbing many neutrons .

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x would be the most and the least would be y because there are more fruit   and seeds than flock z has insects

energy and particles