50kg正常成人的血液总量有()
A.2000~2500mL
B.2500~3000mL
C.3000~3500mL
D.3500~4000mL
E.4000~5000mL
参考答案:D
—_____ does your English teacher look like?
—She's short and thin.[ ]
A. What
B. Where
C. Who
D. Which
某中学化学课外活动小组的同学在实验室测定一批生理盐水中NaCl的质量分数。取该生理盐水130克,向其中加入足量的AgNO3溶液完全反应后,生成氯化银沉淀2.87克。计算该生理盐水中NaCl的质量分数。