题目内容
有一光电池，在输入光通量为20μlm时，其开路电压为30V，短路电流为60μA，试求出最佳负载电阻RM？
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根据以下内容回答题：In the United States，it is not customary to telephone someone very early in the morning.If you telephone him early in the day，while he is shaving or having breakfast，the time of the call shows that the matter is very important and requires immediate attention．The same mean-ing is attached to telephone calls made after l l：00 P．m．If someone receives a call during sleeping hours，he assumes it"s a matter of life ot death．The time chosen for the call communi-cares has its importance． In social life，time plays a very important part ineveryday life．In the U．S．A．guests tend to feel they are not highly regarded if the invitation to a dinner party is extended only three or four davs before the party date．But it is not true in all countries．In other areas of the world，it may be considered foolish to make an appointment too far in advance because plans which are made for a date more than a week away tend to be forgotten．The meaning of time differs in dif-ferent Darts of the wodd．Thus，misunderstandings arise between people from cultures that treat time differentlv．Promptness is valued highly in American life．If people are not prompt，they may be regarded as impolite or not fully responsible．In the U．S．no one would think of keep-ing a business associate waiting for an hour，it would be too impolite．A person who is 5 mi-nutes late．he wm say a few words of explaination，though perhaps he will not complete the sentence
“The same meaning is attached to telephone calls made after 11：00 P．m…”Here “attached”means
某光电导的弛豫时间为3×10-3s，当光生载流子寿命为10-6s时，问该光电导材料有无陷阱，若有，则求出载流子在陷阱上的时间？
依据《注册安全工程师管理规定》，为了保证注册安全工程师的执业水平，注册安全工程师在每个注册周期内应当参加由具备资质的安全生产培训机构实施的继续教育，培训时间累计不得少于()。
某5000位线阵CCD，其两像元中心间距为7μm，像元高度10μm，试求：
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