Locus

Circle with center at origin and radius 3, Perpendicular bisector of a line segment, Angle bisector of two intersecting lines, A single point

A locus is the set of all points satisfying a given condition. A circle, perpendicular bisector, angle bisector, and even a single point can all be loci depending on the conditions. However, the entire plane cannot be a locus as it doesn't satisfy any specific geometric condition.

The angle bisector of angle A

The locus of points equidistant from two intersecting lines (sides AB and AC) is the angle bisector. Since AB and AC intersect at vertex A, the angle bisector of angle A contains all points equidistant from these two sides.

True

This statement is true for the perpendicular bisector locus. By definition, the perpendicular bisector of a line segment is the locus of all points equidistant from the endpoints. Every point on this locus has equal distance to both given points.

10 cm

When a wheel rolls on a straight road, its center maintains a constant distance from the road equal to the radius of the wheel. Since the wheel has radius 10 cm, the center's locus is a line parallel to the road at distance 10 cm above it.