The diagram shows a pair of parallel lines crossed by two 
intersecting transversals.
a Work out the size of angle a. Give a reason for your answer.
b Work out the size of angle b. Give a reason for your answer.
c Work out the size of angle c. Give a reason for your answer.
d Work out the size of angle d. Give a reason for your answer.
e Work out the size of angle e. Give a reason for your answer