正弦电压υ的幅值为10V,其波形如图所示,施加于容抗Xc=5υ的电容元件上,通过该元件上的电流ic与u取关联正方向,则电流ic=()。
A. 50sin(ωt-90°)A
B. 2sin(ωt+120°)A
C. 50sin(ωt+90°)A
D. 2sin(ωt-120°)A
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电路如图所示,设晶体管工作在放大状态,欲使静态电流Ic减小,则应()。
A. 保持Ucc,RB一定,减小Rc
B. 保持Ucc,Rc一定,增大RB
C. 保持RB,Rc一定,增大Ucc
D. 无法实现
如果通过内部控制测试,发现该公司的内部控制制度极其薄弱,不准备信赖内部控制,在执行中直接运用实质性测试程序,但如果仍然没查出重大错报,此时注册会计师将不会承担重大过失责任。()
A. 正确
B. 错误
党的十一届三中全会以后,我国公安机关不断探索建立与社会主义市场经济相适应的公安工作运行机制、队伍管理体制和警务保障机制()。
A. 正确
B. 错误
Section B
Directions: This section is to test your ability to understand short conversations. There are 2 recorded conversations in it. After each conversation, there are some recorded questions. The conversations and the questions will be spoken only once. When you hear a question, you should choose the correct answer from the 4 choices marked A, B, C, and D.
听力原文:W: Look, Bert. My tapes always get stuck in the player.
M: Why not get an MP3 player?
W: A what?
M: An MP3 player. It's the latest thing in digital audio technology.
W: What do you mean "digital audio technology?"
M: MP3 format is a new way of compressing large audio files into a much smaller size. Using the Internet, you can download songs in MP3 format and then play them back whenever you want.
W: Do you have to use the Internet to use MP3 technology?
M: Not necessarily. Using MP3 technology, I recorded my whole CD collection into my computer and now I listen to music while playing computer games!
(6)
A. Her tapes often get stuck in her tape player.
B. She doesn't understand what the man says.
C. She can't repair her tape player.
D. She doesn't have the money to buy an MP3 player.