Manny uses a sprinkler system to water his lawn. Each lawn sprinkler sprays a distance of 10 feet in every direction. One lawn sprinkler is broken and is only spraying four fifths of the area it usually covers. How many square feet of the yard is being watered by the broken sprinkler? Leave the answer in terms of π.
8π square feet
16π square feet
80π square feet
125π square feet