A:无机盐 氧气
B:有机物 能量
C:氧气 尿素
D:叶绿素 光能
A. He is wearing a yellow T-shirt and a cap.
B. She is wearing a skirt and a nice scarf.
C. He is wearing a black coat.
D. She is wearing gloves.
下列海区中,大洋环流呈顺时针方向流动的是 ( )
铝与稀硫酸反应的速率较慢,下列措施不能加快反应速率的是( )
土壤肥力高低的重要标志是( )