单选题某校今年的毕业生中，本科生和硕士生人数之比为5:2，据5月份统计，本科生有70%，硕士生有90%已经落实了工作单位，此时，尚未落实工作单位的本科生和硕士生人数之比是( ). (A)35:18 (B)15:2 (C)8:3 (D)10:3 (E)A、B、C、D都不正确

单选题若，则满足条件的常数a，b为______．A．-1，3B．1，3C．-1，-3D．1，-3

单选题车间共有40人，某技术操作考核的平均成绩为80分，其中男工平均成绩为83分，女工平均成绩为78分．则该车间有女工______人．

单选题某一批花生种子，如果每1粒发芽的概率为，那么播下4粒种子恰有2粒发芽的概率是______A．B．C．D．E．

单选题设A为m×n矩阵，以下命题正确的是( )

单选题f(x)有最小值2．

单选题如abc≠1，且则______．

单选题曲线

单选题若复数，则|z|=______．A．6B．C．3D．

单选题You're busy filling out the application form for a position you really need, let's assume you once actually completed a couple of years of college work or even that you completed your degree. Isn't it tempting to lie just a little, to claim on the form that your diploma represents a Harvard degree? Or that you finished an extra couple of years back at State University? More and more people are turning to utter deception like this to land their job or to move ahead in their careers, for personnel officers, like most Americans, value degrees from famous schools. A job applicant may have a good education anyway, but he or she assumes that chances of being hired are better with a diploma from a well-known university. Registrars at most well-known colleges say they deal with deceitful claims like these at the rate of about one per week. Personnel officers do check up on degrees listed on application forms, then. If it turns out that an applicant is lying, most colleges are reluctant to accuse the applicant directly. One Ivy League school calls them "impostors". Another refers to them as "special cases". One well-known West Coast school, in perhaps the most delicate phrase of all, says that these claims are made by "no such people". To avoid complete lies, some job-seekers claim that they "attended" or "were associated with" a college or university. After carefully checking, a personnel officer may discover that "attending" means being dismissed after one semester. It may be that "being associated with" a college means that the job-seeker visited his younger brother for a football weekend. One school that keeps records of false claims says that the practice dates back at least to the turn of the century--that's when they began keeping records, anyhow. If you don't want to lie or even stretch the truth, there are companies that will sell you a fake diploma. One company, with officers in New York and on the West Coast, will put your name on a diploma from any number of nonexistent colleges. The price begins at around twenty dollars for a diploma from "Smoot State University". The prices increase rapidly for a degree from the "University of Purdue". As there is no Smoot State and the real school in Indiana is properly called Purdue University, the prices seems rather high for one sheet of paper.

单选题设工x1，x2是关于x的方程x2-(m-1)x-m＝0(m≠0)的两个根，且满足则m的值为( )．