2. Wind, water, and climate.
3. Food, disease, predators
I think the answer to the question is b
Answer:
To absorb neutrons before the neutrons can initiate more fusion reactions.
Explanation:
Control rods, usually made of compounds like graphite, absorb neutrons and prevent them from going everywhere and bombarding other molecules of the radioactive compound being used, usually U-238, and prevent a chain reaction from starting. When U-238 is bombarded with a neutron, it releases 3 others, which hit 3 molecules of U-238, releasing 27 neutrons in total, and so on. This must be controlled, otherwise an uncontrolled chain reaction could easily become highly explosive (Nuclear bombs that utilise U-238 use this principle to cause a chain reaction at a larger scale that releases huge amounts of energy that cause the initial explosion when the atom bomb is detonated).
Petri (the person that invented the Petri dish) invented the transparent glass lidded dishes which were meant for keeping and growing bacteria and other stuff including fungi and mosses sterilized. It dated back to the late 1800s.
The area of the brain that the nurse would be concerned about when finding to a woman who explain that she has been very unsteady and has difficulty in maintaining balance is cerebellum. Cerebellum is responsible in coordinate voluntary movement
