钠吸附比
参考答案:
溶液中Na+浓度与Ca2+、Mg2+浓度之和的平方根的比值。
“善师四夷者,能治四夷;不善师夷者,外夷制之。“这种思想最早出现在[ ]
A、
B、
C、
D、
He wants to see changes in the company and I am sure he will ______. [ ]
A. on time
B. at a time
C. at one time
D. in time