题干

根据已给出的入射光和出射光,请在方框内画出合适的透镜.

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答案(点此获取答案解析)

解:折射光线与入射光线相比,向主光轴方向偏折,光线会聚了,故填入凸透镜;如图所示:

同类题1

一个国家的发展强大与海洋的开发利用有着密不可分的关系。阅读材料,回答问题。

材料一:中国古代海外贸易历史悠久,它是随着中国社会经济的发展和造船航海业的进步而不断发展的,成为古代中国对外经济联系的一个主要梁道。

——搜狗百科·中国古代海外贸易

材料二:起源于海洋文明的西方国家很早就重视海洋的意义。几百年来,萄萄牙、西班牙、荷兰、英国乃至今天的美国在世界上的优势力量都是以海权为基础的。

——《科普百家论坛:海军武器实录》

材料三:孙中山说:“中国海权一日不兴,则国基一日不宁。”“争太平洋之海权,即争太平洋之门户权。人方以我为争(意为别国以我国为争夺瓜分的对象),岂置之不问。”孙中山面对旧中国的形势,从民族存亡和民生的角度关注海洋,在《实业计划自序》中说:“操之在我则存,操之在人则亡。”

——杨金森、范中义《中国海防史》

材料四:有的学者从中国面临20世纪80年代世界第二次重大产业梯度转移出发,提出只有采取率先加快沿海地区对外开放的战略,才能抓住这个难得的机遇。“因为内地无论从区位上、与海外的联系上还是从工业基础上、科学技术水平上、劳动者的素质上,都与沿海存在差距。能较快扩大开放,转换机制,吸引海外资金和技术,吸收和借鉴外国一切反映现代社会化生产规律的先进经营方式、管理方法、率先接收东亚地区第二次重大产业样度转移的,还是沿海地区。”

——夏禹龙《加速发展、达到共同富裕的捷径》

同类题4

阅读理解

    Homestay provides English language students the opportunity to speak English outside the classroom and the experience of being part of a British home.

    What to Expect

    The host will provide accommodation and meals. Rooms will be cleaned and bedcovers changed at least once a week. You will be given the house key and the host is there to offer help and advice as well as to take an interest in your physical and mental health.

    Accommodation Zones

    Homestays are located in London mainly in Zones 2, 3 and 4 of the transport system. Most hosts do not live in the town center as much of central London is commercial and not residential. Zones 3 and 4 often offer larger accommodation in a less crowded area. It is very convenient to travel in London by underground.

Meal Plans Available

*Continental Breakfast

*Breakfast and Dinner

*Breakfast Packed Lunch and Dinner

    It's important to note that few English families still provide a traditional cooked breakfast. Your accommodation includes Continental Breakfast which normally consists of fruit juice, cereal, bread and tea or coffee. Cheese, fruit and cold meat are not normally part of a Continental Breakfast in England. Dinners usually consist of meat or fish with vegetables followed by dessert, fruit and coffee.

Friends

    If you wish to invite a friend over to visit, you must first ask your host's permission. You have no right to entertain friends in a family home as some families feel it is an invasion(侵犯) of their privacy.

    Self Catering Accommodation in Private Homes

    Accommodation on a room-only basis includes shared kitchen and bathroom facilities (设施) and often a main living room. This kind of accommodation offers an independent lifestyle and is more suitable for the long-stay student. However, it does not provide the same family atmosphere as an ordinary homestay and may not benefit those who need to practice English at home quite as much.