80∶      =400∶50（    ）

C

    There are over 800 boarding schools in the UK with students from home and foreign countries. Boarding schools started hundreds of years ago in the country. But the earliest boarding schools were set up for white, rich boys only. Now both boys and girls can go to boarding schools from the age of 7 to 18.

    What to do?

    In the UK, boarding schools have three terms in a school year, with about 13 weeks in each term. Students study and live together. They can't go outside if they are not allowed to. In some schools, each student has his or her subject plan. Besides the usual classrooms and laboratories, the boarding schools have lots of other facilities for their students, including music rooms, boats, swimming pools, cinemas and theatres. Most boarding schools have a "light-out" time. So when it's time to go to bed, all the lights in the bedrooms are turned off. There are house-masters to take care of students all the time, especially after school hours.

    What to wear?

Nearly all students at boarding schools wear a school uniform. Boys usually wear a shirt and a tie, and girls wear a white blouse, sometimes also a tie and a skirt. As students get older, the rules become less strict.

    ____________?

    In the UK, boarding schools provide students with delicious food. They can choose to have a full English breakfast or simply bread. They can also choose between a meal with no meat and another meal at lunch and dinner. And there is always self-service for salad (沙拉), other side dishes and a dessert. Students can also make themselves something to eat at any time in a kitchen, or drink tea or have a snack between meals.

我国首批经济特区中与其他三个不在同一个省的是（    ）

已知$F_1,F_2$是椭圆$x^2+2y^2=6$的两个焦点，点M在此椭圆上且$\angle F_{1}M{F}_2=60°$，则$△M{F}_1{F}_2$的面积等于（    ）