题目

甲、乙两种晶体(不含结晶水)的溶解度曲线如下图     所示。   (1)t2℃时将20 g甲加人100 g水中，充分搅拌后的溶液是                  溶液(填“饱和”或“不饱和”)。   (2)将t2℃时乙的某不饱和溶液降温到t1℃时恰好达到饱  和状态，该过程中溶质的质量      (填“减小”、       “不变”或“增大，’)。   (3)将t2℃时甲、乙晶体的饱和溶液分别蒸发等量水后，       复至t2℃，甲溶液析出晶体的质量       (填“>”、 “=”或University Students 　　Full-time university students spend all their time studying. They don't do other work. Their course (课程) usually lasts for three or four years. Medical students have to follow a course lasting for six or seven years. Then they graduate (毕业) as doctors. In Britain, full-time university students have three terms of about ten weeks in each year. During these terms they go to lectures or they study by themselves. Their vacations(假期) are long, but of course they can use them to study at home. 　　Some universities, like Oxford and Cambridge in England, are residential (住校的). This means that during the university terms the students live in universities. 　　Other universities are non-residential. Some of the students at these universities can live in a university hostel(招待所), but many live at home or in lodgings(临时住所) and have to travel daily to their lectures. Large cities often have universities of this kind. Sometimes the students have to spend quite a lot of time on their journeys. 　　Full-time students are also called internal students, because they spend all their time at university. There are also external students who cannot attend the university full-time but who are studying for its examinations. They are part-time students. They have to do other work during the day, usually to earn their living, and they study in the evening. 　　External students are often older than full-time internal students. Sometimes they can attend lectures in the evening, but many of them have to study by correspondence (通信). They write at home the work that is set by their tutors(导师). Then they have to post this work to their tutors and the tutors post corrections and advice back to them. 　　In some countries, “Universities of the Air” can now help students to gain degrees(学位). After special lectures on radio or television, these students too have to send set work for correction by correspondence. However, for a few weeks each year they can attend special vacation courses at universities. 1．________ have to study at university for six or seven years. [　　] A．All the studentsB．Medical students C．Full-time studentsD．Part-time students 2．Medical students all become doctors ________ . [　　] A．when they graduate B．before they graduate C．after they work in the hospital for six or seven years D．while they are studying at universities 3．The residential students are those who ________ . [　　] A．live at homeB．go to school every day C．live in a universityD．have to do other work 4．The part-time students ________ . [　　] A．work for a living in the daytime and study in the evening B．are internal students C．are residential students D．have to attend lectures during the day 5．Correspondence is ________ . [　　] A．a course for older students B．a course for internal students C．a course for the residential students D．a course whose students send their work by post to their tutors 6．The students of “Universities of the Air” ________ . [　　] A．study as the internal students B．study by air C．attend lectures in the evening D．can attend lectures on radio or television