【简答题】静电场的环路定理的数学表示式为: 该式的物理意义是:单位正电荷在静电场中沿任意闭合路径绕行一周, __________ 力作功等于零。
【简答题】人体血液的pH总是维持在7.35~7.45的范围内,这是由于 (A) 人体内有大量的水分(约占体重的70%) (B) 新陈代谢的CO 2 部分溶解在血液中 (C) 新陈代谢的酸碱物质适量地溶解在血液中 (D) 血液中的 和H 2 CO 3 只允许一定的比例范围
【单选题】While ______ in the supermarket, I met an old friend of mine.
【单选题】______ of danger on the road at night ,the girl had to go home with a friend _______ her.
A.
Being warned; accompanied
B.
Having warned; accompanying
D.
Having been warned; accompanying
【单选题】人体血液的pH总是维持在7.35~7.45。这是由于
【判断题】结跏跌坐:双足交叉于左右膝上(双盘坐),如果单以右足压于左腿之上(俗称单盘)。
【单选题】The girl was quite angry ______ his boy friend for his being late.
【判断题】人员推销这种促销方式说服力小,难以促成当面交易( )A. 对 B. 错
【单选题】_____ of danger in the street at night, she had to go home with a friend _____ her.
A.
Being warned; accompanied
B.
Having warned; accompanying
D.
Having been warned; accompanying
【单选题】人体血液的pH总是维持在7.35~7.45,这是由于()。
B.
血液中的HCO 3 和H 2 CO 3 起缓冲作用