PHS-3C型酸度计工作原理?
参考答案:
是利用PH电极和参比电极对被测溶液中不同酸度产生的直流电位,通过放大器输送到转换器,以达到显示PH的目的。
The professor said he could talk on ()interested the audience.
A.any topic
B.which topic
C.whichever topic
D.the topic he thought it
女性体内脂肪较多,而且水分含量比男性高。( )