下列有关物质性质的应用正确的是（　　）

算一算，连一连。

1600－600  3500－3000  4100－700  600＋300

2700－2000  700＋600  1600－400  200＋800

2015年3月29日以来，我国海军护航编队为保护中国公民生命财产安全，根据中国政府统一部署，成功从____撤离了613名中国公民，以及来自15个国家的外国公民279人，充分体现了中国政府“以人为本”的理念和国际主义、人道主义精神。（    ）

阅读下列短文,从每小题所给的A、B、C、D四个选项中选出一个最佳选项。

    Tu Youyou, aged 85, is a medical scientist at the China Academy of Traditional Chinese Medicine. she has just become the first Chinese woman to win a Nobel prize, for helping discover artemisinin, a new kind of medicine known as "Qing-hao-su" in Chinese in 1971 and dihydroartemisinin, used also to treat malaria(疟疾).

    The discovery of “Qing-hao-su” and its use in treating malaria are regarded as the most important breakthrough(突破) in tropical medicine in the 20th century. It is also a major health improvement for people in developing tropical countries in south Asia, Africa, and South America.

    This is the first time her work has been widely recognized in China, and it also marks the first time China has won a Nobel prize in the sciences.The last time a Chinese national won a Nobel Prize was in 2012, when Mo Yan got the literature award.

    Tu also received several medical awards in the past including the 2011 Lasker Award in Clinical Medicine for the same achievements.Tu was the first native Chinese who was educated and works in China to win the Lasker award, too.

在小兰14岁生日这天,妈妈对她说：孩子，妈妈虽然非常爱你，但你总是会长大的，从现在起你要学会承担责任。身边的亲人、朋友、老师会告诉你怎样生活、怎 样做人，但采取任何行动之前，你都要认真思考：任何行动会给你带来什么结果，怎样才能把事情做得更好。妈妈这是在教导（   ）
①要有勇气和智慧选择自己承担的责任②要选择自立自强的人生③要对承担责任的代价和回报进行正确评估,作出最合理的选择④只要会付出代价的责任就不要承担