题干

请按要求作图:

①请在图(1)中画出重物上升,最省力的绕线方法;

②如图(2),木棒在力F的作用下静止,画出力F关于O点的力臂;

③如图(3),请将图中的灯、开关正确连入家庭电路.

     

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    A girl complained to her father about her hard life. She didn't know what she had to do and wanted to1up. She felt tired of fighting and fighting. One problem had been finished but2came over.

    Her father, a cook, took her into the3.He poured water into three pans (锅) and boiled it. When the water was boiling, in the first pan he put some carrots, in the second he put some eggs and in the last he put some coffee. He 4for them for a few minutes without any words.

    The girl waited impatiently, not knowing5her father was doing that. About 20 minutes later, her father turned6the stove, took out the carrots and put them in a bowl. He took out the7and put them in another bowl. After that the coffee was poured into a cup. Turning back to his daughter, he asked, “My sweet heart, what do you8?” “Carrots, eggs and coffee,” she answered.

    Her father told her to 9her eyes and let her touch the carrots. She did so and felt that the carrots were10. After that he asked her to take eggs and11them. Then, she got the eggs, warm and hard. At last, the father asked her to smell the coffee. She asked, “What did you do this for, Father?” He12that each one had had the same unlucky experience—the boiling water, but13had a different result. The strong and hard carrots had become soft and weak after being in the boiling water. The eggs became hard after being cooked. The coffee was very14and it changed the water. “Who are you?” asked her father, “When bad luck15your door, what's your decision? Are you carrots, eggs or coffee?”