<em>Coplanar</em> means "lying on the same plane," while <em>colinear </em>means "lying on the same line." In this problem, all four points A, B, C, and D are coplanar - they all lie on the plane - so we just need to find the points that lie on the same line. Though points C and B <em>would </em>be colinear if there was a line drawn between them, there's no such line in this problem, so we can rule that out. We notice one line drawn on the plane, and points A, C, and D lying on it, so we can say that points A, C, and D are both coplanar and colinear.
There can only be less than or equal to 125 customers, you can't have more than that but you can have exactly 125 or less than 125. your inequality should look like < 125 with a line underneath the symbol to describe "equal to"
