“任何生物如果能以任何方式发生纵然微小但有利于自己的变异，它在复杂的而且时代变化的生活条件下，就会获得较好的生存机会，因而它就自然地被选择了。”提出这一理论的科学家是（    ）

如图，灯L₁、L₂分别标有“6V，6W”和“6V，3W”的字样，当开关都闭合时两灯都正常发光，则通过L₁和L₂的电流之比是（　　）

下图为时政漫画《奥卿也疯狂》。其主旨是（    ）

    Hi, friends!My name is Jason．I am 11 years old and I live in Chicago in the USA．There are many holidays every year,and，my favorite one is Thanksgiving(感恩节)．It is a family holiday．

    Thanksgiving comes on the fourth Thursday of November every year．There is no school on Thanksgiving Day．That's great!My family gets together on Thanksgiving Day．My brother will drive home from New York．We always have a big dinner．My mom makes a lot of delicious food．My sister always helps her in the kitchen．We have roast turkey,sweet potatoes,pumpkinpie(烤火鸡，红薯，南瓜派)and so on．Turkey is a must in my family．Before dinner we give thanks to everything

wehave．

    I love this holiday very much．It teaches me to be thankful in life．My favorite thing about the holiday is being with my family and having a great time with them．That is a very important thing of the holiday．

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