【多选题】造成三元催化转化器的催化剂热失活的原因有( )。
【简答题】设A=[1 2 3;3 0 1;4 1 2],B=[2 0 0;-1 5 0; 1 9 -6],试编写程序求解下列问题 (1)求AB 的行列式; (2)提取矩阵B(A+B)的第2条对角线元素; (3)求解矩阵方程BX=2A-3E; (4)求矩阵4A+2B的特征值U与特征向量V。
【单选题】None of the people who gave blood are people who were tested, so everybody who gave blood must have been untested.
【简答题】造成重整催化剂失活的原因有()、()、()和()。
【判断题】按FOB和FCA术语成交,应由买方订立运输合同或指定承运人。按惯例,当卖方被要求协助订立运输合同时,只要买方承担费用和风险,卖方也可以办理。( )
【简答题】Everybody who ______ (wear) glasses will tell you their eyes have gradually got worse over time.
【单选题】FOB和FCA术语成交,应由买方订立运输合同或指定承运人。按惯例,当卖方被要求协助订立运输合同时,只要买方承担费用和风险,卖方也可以办理。( )
【简答题】Passwords are a way of life for nearly everybody who uses any kind of software. It makes a password-management program a favorite option for modern people. →Passwords are a way of life for nearly ever...
【判断题】按FOB和FCA术语成交,应由买方订立运输合同或指定承运人。按惯例,当卖方被要求协助订立运输合同时,只要买方承担费用和风险,卖方也可以办理。( )