单项选择题 求不定积分，可做代换(   ),消去根号，从而求得答案 A. B. C. D. 以上答案均不正确

问答题 What is the reason for women to have plastic surgery? A、To please their husbands. B、To gain self-confidence. C、To find a better job. D、To impress other people.

单项选择题 In photosynthesis, A、Carbon dioxide and water are used to produce glucose. B、Glucose is broken down into carbon dioxide and water. C、Energy stored in organic matter is transferred to ATP. D、Carbon is converted to an inorganic form.