【单选题】He is always here. It's ______ you've never met him.
【判断题】采用直缩法生产PET树脂,原料对苯二甲酸与乙二醇的酯化反应温度通常是在乙二醇的常压沸点以下。
【单选题】听力原文:When are we meeting? (A) Tomorrow afternoon. (B) I've never met him before. (C) No, I don't know when it's due. (13)
【单选题】'Have you met Bill's brothers?''I've met one. I didn't know he had_________.'
【简答题】He is always here it’s ________ you’ve never met him. A) unique B) strange C) rare D) peculiar
【简答题】患者,男,38岁,车祸伤及头部,当即出现右侧鼻唇沟变浅,右外耳道流出淡血性液体, 右耳听力下降,CT显示颅内少量积气。考虑患者出现了A. 颅前窝骨折B. 颅中窝骨折C. 颅中窝骨折D. 额骨骨折E. 脑挫裂伤
【单选题】患者,男,38 岁,车祸伤及头部,当即出现右侧鼻唇沟变浅,右外耳道流出淡血性液体,右耳听力下降,CT 显示颅内少量积气。考虑患者出现了
【单选题】如图所示,细杆OA绕齿轮1的中心轴O转动,转速n已知。在细杆上安装有齿轮2、3,细杆转动过程中三个齿轮两两相互啮合,齿轮1固定不动,齿轮2、3转动。三个齿轮的半径r1、r2、r3已知,且r1=r3,求齿轮2、3各自的角速度。 【图片】
A.
n 2 =(2 r 1 + 3 r 2 )/ r 2 * n , n 3 =(2 r 1 + r 2 )/ r 2 * n
B.
n 2 =( r 1 + 2 r 2 )/ r 2 * n , n 3 = n
C.
n 2 =( r 1 + r 2 )/ r 2 * n , n 3 = 0
D.
n 2 =(2 r 1 + r 2 )/ r 2 * n , n 3 =2 n