磷矿粉(groundphosphaterock)性质
参考答案:
灰褐色或黑褐色粉末;难溶于水;呈化学中性;同晶置换程度与直接施用的肥效显著相关。
细胞膜是可兴奋膜,有接受刺激、()的功能。
The()controls the cursor or pointer on the screen and allows the user to access commands by pointing and clicking.
A.graphics
B.printer
C.program
D.mouse