Angle θ is positioned in a circle with its initial ray on the positive x-axis and its terminal ray 1/3 of one complete revolution about the origin, as shown in the following diagram. What is the measure of angle θ, in degrees and in radians? Select one answer.
A
60and π/3 radians
B
60 and 2π/3 radians
C
120 and π/3 radians
D
120 and 2π/3 radians

Statement reason 1. δabc is similar to δced. given 2. 3. definition of slope 4. slope of slope of definition of slope 5. slope of × slope of multiplying the slopes 6. slope of × slope of substitution property of equality 7. slope of × slope of simplifying the right side the table contains the proof of the relationship between the slopes of two perpendicular lines. what is the reason for statement 2? a. parallel line segments that meet a common perpendicular line are proportional in length. b. the lengths of vertical and horizontal sides in congruent triangles are in a common ratio. c. trigonometric identities determine the lengths of the legs in a right triangle. d. corresponding side lengths in similar triangles are proportional in length.