A straight jogging track EF intersects two straight walkways AB and CD at points P and Q respectively. The acute angle between EF and AB that lies inside the region between AB and CD is 68∘. The angle on the opposite side of EF at Q that also lies inside the region between AB and CD is (2y+4)∘.
a. (i) If the two walkways AB and CD are required to be parallel for safety reasons, form an equation in y and find its value.
b. (ii) For the value of y obtained in part (i), calculate the magnitude of the angle at Q.
c. (iii) If instead y=30, determine whether AB and CD would be parallel. Give a reason for your answer.