Suppose Hayley decides to see the lions. Which result would be a cost?

 - Hayley will enjoy seeing the lions more than she would have enjoyed seeing the gorillas.
 - Hayley will spend more time walking to the lions. They are on the other side of the zoo, but the gorillas are close by.
This result is a cost. It involves giving up or spending something that Hayley wants or needs:
Hayley will spend more time walking to the lions. They are on the other side of the zoo, but the gorillas are close by.