Answer:
A.
Explanation:
the gradual movement of the continents across the earth's surface through geological time.
Answer:
By minimizing the height of the body's center of gravity relative to its center of buoyancy
Explanation:
In hydrostatics, the equilibrium state of a floating body relates to either a maximum or minimum of the potential energy.An equilibrium is stable when the potential energy is minimum.Minimizing the height of the floating body's center of gravity relative to its center of buoyancy attains a stable equilibrium configuration.
The wavelength is the distance between one crest/trough to another crest/trough. On the image, it's basically the length between each peak of the wave. You can see that the distance between peaks in wave A are much shorter than the distance between the peaks in wave B.
Thus, wave B has the longer wavelength.
The oxidation is occurring on Calcium ions as it release one electron and reduction will be occurring on fluorine ion as it accepts one electron.
<u>Explanation:</u>
An element will undergo oxidation and form a positive ion on releasing one or more electrons from its valence shell. While reduction is occurred in a chemical reaction, then the element will be forming a negative ion with the acceptance of one or more electrons in its valence shell.
So in the given process of calcium fluoride, the one electron from the valence shell of calcium will be released making it as 
ions and this is termed as oxidation process. This one electron will be getting accepted by the fluorine ion and thus it will convert to 
ions. This process of acceptance of electrons is termed as reduction.
They use it because it's standerize and evidence vase
