<span>All the processes that physically disintegrate or chemically decompose a rock at or near the earth's surface is called w</span>eathering.
<span>Weathering produces sediment, whereas erosion transfers sediment from place to place.</span>
The crystal structure of an ionic compound depends on the sizes of cations and anions, as well as the ratio of cations to anions. The ratio of the cations and anions need to be even, otherwise, the crystal won't form.
So the answer would be D, both A and B.
It is the symbol used to represent nano meters.
Hope This Helps You!
Good Luck Studying :)