A) Mot hinh lap Phuong co canh 4 cm. Neu canh hinh lap Phuong do tang gap 2 lan thi dien tich toan Phan cua no gap len may lan
B) Mot hinh lap Phuong co tong dien tich xung quanh .ca dien tich toan phan la 640 cm v uong. Vay canh cua hinh lap Phuong do la bao nhieu