The problem asks us to determine, using a protractor (which is unavailable, so visual estimation will be used instead), whether the lines in each of the four figures (a, b, c, and d) are perpendicular. Perpendicular lines intersect at a right angle, which is 90 degrees.

1. Problem Description

The problem asks us to determine, using a protractor (which is unavailable, so visual estimation will be used instead), whether the lines in each of the four figures (a, b, c, and d) are perpendicular. Perpendicular lines intersect at a right angle, which is 90 degrees.

2. Solution Steps

Since I do not have a protractor, I will visually estimate the angles between the lines in each figure.

a) The lines appear to intersect at approximately 45-degree angles, which are not right angles. Therefore, the lines are not perpendicular.

b) The lines appear to form a right angle. Therefore, the lines are perpendicular.

c) The lines appear to intersect at right angles. Therefore, the lines are perpendicular.

d) The lines appear to intersect at an angle that is not a right angle. Therefore, the lines are not perpendicular.

3. Final Answer

a) Not perpendicular

b) Perpendicular

c) Perpendicular

d) Not perpendicular