题目

—How can you keep slim as a mother of two? —I have been ________ in the gym for years. A. working out       B. carrying out     C. getting out          D. giving out 答案：A5．t℃时，硝酸钾溶液200g，蒸发20g水后，析出晶体8g；又蒸发20g水后，析出晶体12g．t℃时，硝酸钾的溶解度是多少？