题目

如图所示，重力G＝20N的物体，在动摩擦因数为0.1的水平面上向左运动，同时受到大小为10N，方向向右的水平力F的作用，则物体所受摩擦力大小和方向是     A．2N，水平向左 B．2N，水平向右C．10N，水平向左    D．8N，水平向右 答案：B 根据对话内容，从对话后的选项中选出适当的选项补全对话，并将选项的编号依次填入题后横线上。 A：Hello, Maria!Haven't seen you for a long time． B：I'm busy these days． A：What a beautiful new skirt you wear today! B：Thank you．　　1　　 A：Of course．Where did you buy it? B：　　2　　 A：You didn't buy it?Is it a gift from your parents? B：No．　　3　　 A：Really?I can't believe it! B：　　4　　 I enjoy making clothes by myself．My mother is really good at making clothes and she taught me a lot about it．　　5　　 The color and design were very nice to me．I made a skirt with it by myself．A：Wow, what a clever girl you are! A．I didn't buy it． B．Last Sunday I bought a piece of cloth(布)． C．I'm not kidding． D．I made it by myself． E．Do you really think so?