将x4﹣2x2+1因式分解的最终结果是____ .
--- Where's your cousin?
--- He his homework in his bedroom.
— There is little water left in the bottle, ______?— No, we need to buy some more before we run out of it.
下列大洲中，被太平洋、大西洋、北冰洋包围的是
