Which of the following statements is true?
a. In parallel lines, the distance between the lines and fixed and the two lines are going in the same direction.
b. Perpendicular lines are lines that meet at a point. When two lines intersect, they define angles at the point of intersection.
c. Skew lines are lines that are coplanar and can never intersect at any given point.
d. Two lines intersect at more than one point and they define angles at the point of intersection.​