题干

两物体A,B从同一位置出发,如图所示为两物体作直线运动时的图像,但纵坐标表示的物理量未标出,则以下判断正确的是(   )

A:若纵坐标表示位移,则A质点以2m/s的速度匀速运动

B:若纵坐标表示位移,B质点先沿正方向做直线运动,后沿负方向做直线运动

C:若纵坐标表示速度,则B物体加速度先减小再增加

D:若纵坐标表示速度,则在t=4s时刻,两物体相遇

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A,B,C

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    Generally speaking, college graduation brings both the satisfaction of academic achievement and the expectation of a well-paid job. But for 6,000 graduates at San Jose State this year, there's uncertainty as they enter one of the worst job markets in decades.

    Ryan Stewart has a freshly minted degree in religious studies, but no job prospects. “You look at everybody's parents and neighbors, and they're getting laid off and don't have jobs,” said Stewart. “Then you look at the young people just coming into the workforce.., it's just scary.”

    When those graduates entered college, the future never looked brighter. But in the four years they've been here, the world outside has changed dramatically. “Those were the exciting times, lots of dot-com opportunities, exploding offers, students getting top dollar with lots of benefits,” said Cheryl Allmen-Vinnidge, of the San Jose State Career Centre. “Times have changed. It's a new market. The job situation is grim (严峻的) now.” Cheryl Allmen-Vinnidge ought to know. She runs the San Jose State Career Centre, (it is) sort of a crossroads between college and the real world. Allmen-Vinnidge says students who do find jobs after college have done their homework. “The typical graduate who does have a job offer started working on it two years ago. They've postured themselves well during the summer. They've had several internships (实习) ,” she said. And they've majored in one of the few fields that are still hot—like chemical engineering, accounting or nursing—where average starting salaries have actually increased over last year. Other popular fields (like information systems management, computer science, and political science) have seen big declines in starting salaries.

    Ryan Stewart (he had hoped to become a teacher) may just end up going back to school. “I'd like to teach college some day and that requires more schooling, which would be great in a bad economy,” he said.

    It is true more students are able to receive college education. It is also true that they will have to face fiercer competition in the job market as they graduate. It becomes harder and harder for the current graduates to get a foothold in job markets, but many of them have no choice but to follow the beaten track. To some students a degree may not be ticket to instant wealth. For now, they can only hope its value will increase over time.