Answer: -240,000 acres
Explanation:
Given : About 60,000 acres of wetlands are lost each year in the United States .
Then the change in wetlands after 4 years will be :-

We can write is as " About 240,000 acres of wetlands are lost in 4 years in the United States ."
In integer, The change in wetlands after 4 years= -240,000 acres