【简答题】Here are several means of transportation for you to choose when travelling around China. Most parts of China can 1. __________(reach) by rail, 2. _________ is efficient but overcrowded sometimes. You ...
【单选题】在普通车床上用三爪卡盘夹工件外圆车内孔,车后发现内孔与外圆不同轴,其最可能原因是( )
【单选题】Choose the word or phrase that can replace the underlined par in each sentence without changing its original meaning. Sea snakes inject a poison so strong that it kills a fish instantly .
【单选题】Directions: Choose the word or phrase that can replace the underlined part in each sentence without changing its original meaning. Sea snakes inject a poison so strong that it kills a fish instantly .
【单选题】对于线性规划的原问题及对偶问题,下述说法错误的是( )。
A.
当原问题目标函数为最大化,其对偶问题目标函数为最小化
B.
若原问题 m 个变量都为自由变量,那么对偶问题 m 个约束条件都必须是等式
C.
若原问题 n 个约束条件都非负,那么对偶问题 n 个变量也都非负
D.
若原问题为 n 个约束 m 个变量,那么对偶问题为 m 个约束 n 个变量
【单选题】在普通车床上用三爪卡盘夹工件外圆车内孔,车后发现内孔与外圆不同轴,其原因可能是()
【判断题】职业中介机构或者用人单位可以向劳动者收取适当押金。( )
【判断题】劳动者与用人单位订立劳动合同时,用人单位可以要求收取押金或是扣留相关的证件。 ( )