题干

在如图所示的电路中,电源电压为6V,R1=4Ω,只闭合开关S1后,电压表的示数为4V,则电流表的示数为 ____A,电阻R2的阻值为 ____Ω.若同时闭合开关S1、S2,则电流表的示数 ____,电压表的示数 ____(均选填“变大”、“变小”或“不变”).

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1,2,变大,变大

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    As I walked into the primary school, I looked down at my new black Mary Jane shoes—I wanted to be anywhere in the world but Fountain Inn Elementary School. I stood at Mrs. Blackstone's door. Before I tried the1, the wooden door suddenly opened. "We've been waiting for you!" Mrs. Blackstone, my new fifth grade teacher said at an unusually2voice. With a smile my mom walked away and I was left3in front of a group of students.

    Over the next few days, Mrs. Blackstone made it her4to find me a new best friend and help me join a choir(合唱队). During history5, when I sat down at my desk6I didn't want to speak in front of the class, she would not only call on me but have me stand up to7my classmates. She laughed at my nervousness when I wouldn't get in line to sharpen my pencil 8being embarrassed. Her silliness made me smile and finally feel9in the new environment.

    One spring afternoon, Mrs. Blackstone 10me to stay after class. "I'd like to speak with you, Amanda." My mind 11. Had I made a bad grade? Had I hurt someone's feelings? "Are you enjoying your new school?" she sat comfortably behind her desk, "I want to tell you12, between you and me, not to be shared with anyone else." "Okay." My throat 13felt very dry. With her14raised, she said, "I see something15in you. I've been a teacher for over twenty-five years; I can16it. But you17believe in yourself. That's very important. Remember that and you'll go18."

    Her voice was19to my ears that day. I walked out of her class,20staring at my Mary Jane shoes. My teacher saw something special in me!