Answer:
The bones of the skull and spinal column
Explanation:
The central nervous system is better protected than any other system or organ in the body. Its main line of defense is the bones of the skull and spinal column, which create a hard physical barrier to injury.
Answer:
When the electron changes levels, it decreases energy and the atom emits photons. The photon is emitted with the electron moving from a higher energy level to a lower energy level. The energy of the photon is the exact energy that is lost by the electron moving to its lower energy level.
Explanation:
Answer:

Explanation:
Hello,
In this case, it is widely known that when measurements with different significant figures are put under mathematical operations, the final result must be displayed with the same amount of significant figures of the shortest measurement, thus, due to the fact that 5.5 g has two significant figures only the result is consequently shown with two significant figures as well as shown down below:

By rounding the first six to seven due to the fact that the next six is greater than five, according to rounding rules, the result is:

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