20. A square board that has an area of 25 square inches is to be cut into
pieces. each of which is a square with sides of length 1,2 or 3 inches. what is the least number of such square pieces into which the board can be cut ?
A 5
B 6
C 7
D 8
E 9
請問 是不是用依各依各配 配出來答案D.....[/sup]
