纯锌跟稀H2SO4反应速率很小，为了加快锌的溶解和放出H2的速率，可向其中加少量[ ]
A. CuSO4溶液
B. ZnSO4
C. 水
D. 镁条
答案：A
—You've got your flat furnished，haven't you?
—Yes. I some used furniture at the Sunday Market and it was a real bargain. [ ]
A. will buy
B. have bought
C. had bought
D. bought
农民肩扛一把锄头，手握锄头把末端，使锄头水平平衡，如图所示，他感到肩膀压力很大，如果使肩膀受压力小一些，应使锄头在肩膀上的位置向______移动．
