The answers to the given questions are explained below as required:
Part A: Parallel lines are two lines that do not meet. So that the two lines are at an angle of to each other.
ii. A good example that contradicts the definition of parallel lines is the perpendicular lines. Two lines are said to be perpendicular if and only if they are at right angle to each other. Thus, the two lines would be at an angle of to one another.
iii. The definition that would be more accurate is: parallel lines are two lines that do not meet, even when extended till infinity.
Pat B: Undefined terms are terms that can be simply explained by descriptions. Some of the terms are: lines, rays, points etc.
ii. Lines can be used appropriately to illustrate parallel lines.