A line is an endless collection of points that follow a straight path. there is no start and finish and there are no curves.
"imaginary" does not describe a line by definition because lines are definite points, not imaginary ones. "endless" does describe a line because, as stated, they have no start or finish. "curved" does not describe a line, because lines follow a straight path. "has no width" describes a line accurately because lines are one dimensional; when we imagine a line, we visualize it by drawing one with a certain width, but in geometry, lines do not have any width. it's just a representation. a line additionally does not "have two endpoints"--that would be a line segment, with a starting point and a finishing point. lines go on forever in both directions, so you wouldn't be able to find endpoints for it.
I believe the answer is a.
Parent material (what it's made of,) time, climate, relief and organisms are all factors the rate of soil depends on.
<span>Converting a sphere to a flat surface results in distortion. This is the most profound single fact about map projections</span>