Answer:
an explanation that is backed up by evidence
Abrasion takes place when stones become embedded in the glacier, as the glacier moves these stones slowly scratch along the surface of the ground below. Abrasian acts similarly to sandpaper, leaving a fairly smooth surface to the rock it has worn down.
Plucking takes place when the glacier has been fairly stationary for a while, so patches of rock from the ground below have become frozen to the glacier. When the glacier then moves, this patch of ground is forced out of the ground as it is attached to the glacier itself. As you can probably imagine, this leaves behind a much more jagged, uneven surface.
Answer:
Elements and compounds cannot be broken down into simpler substances by an ordinary process because of the following reasons.
1) Elements cannot be broken down by chemical or physical methods because elements is composed of atoms which are indivisible.
2) Compound cannot be broken down into simpler substances by ordinary process because elements present in the compound are combined with each other chemically.
The first one since your doing on the whole neighborhood and not just that one location. You need find the average soil quality and so you need to sample 10 different locations in that neighborhood.