The area of an orchard is about 3 (hectares), and the cover area of a math book is about 3 (square decimeter).

Three hectares is 60 acres. Planting 80~ 100 apples per mu, about 5,000 to 6,000 apples, has a yield of 100 tons, which has a certain scale.

Of course, it is ok to fill in (mu), and it is enough to have a family to pick it.