In order to adequately control the chain reaction in a nuclear power plant, it is necessary to have within the fissionable material a non-fissionable material that neutrons.
a. contributes
b. absorbs
c. reflects
d. emits
e. slows down

B

Explanation:

In a chain reaction of radioactive decay, more and more neutrons are produced that bombard more nuclei causing them to split (decay). This how a nuclear core releases more and more energy. The purity of the radioactive core determines the chain reaction and rate of energy released. A few impurities (nonfissionable material) are introduced to absorb excess  neutrons (and regulate their numbers) to prevent overheating of the core.

a, i am pretty sure.

i believe you meant to say air rather than hair so the answer is below ")

the dead sea, the lowest place on earth at 430 metres (1,410 ft) below sea level, has a correspondingly high typical atmospheric pressure of 1065 hpa.