At the cowchip-throwing contest, each thrower chose their chip ...

[cookcarl]

At the cowchip-throwing contest, each thrower chose their chip according to
  width and weight.
 
  Correct any pronoun use errors in the following sentences by crossing out the
  incorrect pronoun and writing in the correct one above it. In some cases you may
  have to rewrite part of the sentence. If the sentence is correct, do nothing to it.

Question 2

Jack decided to take his wife on a trip to Wyoming rather than buy an expensive
  lens, which impressed his friends.
 
  Correct any pronoun use errors in the following sentences by crossing out the
  incorrect pronoun and writing in the correct one above it. In some cases you may
  have to rewrite part of the sentence. If the sentence is correct, do nothing to it.

[vickyvicksss]

Answer to Question 1

At the cowchip-throwing contest, each thrower chose his or her chip according to width
and weight.

Answer to Question 2

Jack's friends were impressed when he decided to take his wife on a trip to
Wyoming rather than buy an expensive lens.

[cookcarl]

Excellent

[scottmt]

Thanks for the timely response, appreciate it