下列几种说法：①全等三角形的对应边相等；②面积相等的两个三角形全等；③周长相等的两个三角形全等；④全等的两个三角形的面积相等．其中正确的是（ ）

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                                                                                                          论读书
                                                                                                          林语堂
      ①读书本是一种心灵的活动。“万般皆下品，惟有读书高”，读书向来称为雅事乐事。但是现在雅事乐事已经不雅不乐了。今人读书，或为取资格，得学位；或为求爵禄，刮地皮；或为做走狗，拟宣言……诸如此类，皆非读书本旨，在我是看不起的。人之初生，都是好学好问，及其长成，受种种的俗见俗闻所蔽，毛孔骨节，如有一层包膜，失了聪明，逐渐顽腐。读书便是将此层蔽塞聪明的包膜剥下。能将此层剥下，才是读书人。
       ②同一本书，同一读者，一时可读出一时之味道出来。四十学《易》是一种味道，五十而学《易》，又是一种味道。自己见解愈深，学问愈进，愈读得出味道来。也许蒋介石未进过小学，或进小学而未读过地理，或读地理而未觉兴味；然今日之蒋介石翻看闽浙边界地图，便觉津津有味。或某人在狱中读清初犯文字狱的文人传记，才别有一番滋味在心头。
       ③程子谓《论语》读者有此等人与彼等人，有读了全然无事者，亦有读了不知手之舞之足之蹈之者。凡人读书必找一位气质相近的先贤作为老师，这是所谓读书必须得力一家。不可昏头昏脑，听人戏弄。一人同时爱庄荀，或同时爱苏程是不可能的事。找到文学上之情人，必胸中感觉万分痛快，而魂灵上发生猛烈影响，如春雷一鸣，蚕卵孵出，得一新生命，入一新世界。尼采师叔本华，萧伯纳师易卜生，虽皆非及门弟子，而思想相承，影响极大。当二子读叔本华、易卜生时，思想上起了大影响，是其思想萌芽学问生根之始。
                                                                                                                                                         （选自林语堂《论读书》，有删改）

    Across Britain, burnt toast will be served to mothers in bed  this morning as older sons and daughters to deliver their supermarket bunches of flowers, But, according to a new study, we should be placing a higher value on motherhood all year.

    Mothers have long known that their home worked was just heavy as paid work. Now, the new study has shown that if they were paid for their parental labors, they would earn as much as￡172,000 a year.

    The study looked at the range of jobs mothers do, as well as the hours they are working, to determine the figure. This would make their yearly income ￡30, 000 more than the Prime Minister earns.

    By analyzing the numbers, it found the average mother works 119 hours a week,40 of which would usually be paid at a standard rate 79 hours as overtime. After questioning 1,000 mothers with children under 18,it found that ,on most days, mums started their routine work at 7am and finished at around 11pm.

    To calculate just how much mothers would earn from that labor, it suggested some of the roles that mums could take on, including housekeeper, part-time lawyer, personal trainer and entertainer. Being a part-time lawyer, at ￡48.98 an hour, would prove to be the most profitable of the “mum jibs”, with psychologist（心理学家）a close second.

    It also asked mothers about the challenges they face, with 80 percent making emotional（情感的）emand as the hardest thing about motherhood.

Over a third of mums felt they needed more training and around half said they missed going out with friends.

    The study shoes mothers matter all year long and not just on, Mother's Day. The emotional, physical and mental energy mothers devote to their children can be never-ending, but children are also sources of great joy and happiness. Investing（投入）in time for parenting and raising relationships is money well spent.