离子选择电极—流动注射法测定水中氯化物和硝酸盐氮的过程中，如遇气泡聚积在电极表面，应去除，否则影响测定。
参考答案：对
严重高钾血症伴心律失常，应首先（）。
A.口服阳离子交换树脂
B.静脉给予氯化钙
C.紧急血液透析
D.静脉给予葡萄糖+胰岛素
E.静脉输注碳酸氢钠
A jewelry dealer initially offered a bracelet for sale at an asking price that would give a profit to the dealer of 40 percent of the original cost. What was the original cost of the bracelet ？（） (1)After reducing this asking price by 10 percent, the jewelry dealer sold the bracelet at a profit of $403. (2)The Jewelry dealer sold the bracelet for $1,953.
A．条件(1)充分，但条件(2)不充分．
B．条件(2)充分，但条件(1)不充分．
C．条件(1)和(2)单独都不充分，但条件(1)和条件(2)联合起来充分．
D．条件(1)充分，条件(2)也充分．
E．条件(1)和条件(2)单独都不充分，条件(1)和条件(2)联合起来也不充分．
