中国的主要人种是( )
This morning Ella called the manager to say that she was unable to work________a bad cold.
底面直径和高都是4的圆柱的侧面积为( )
某鱼塘的形状是梯形,上底是58m,下底比上底短13m,高12m,这个鱼塘的面积是____ m2 .