问题
判断题
一台变压器用谐振法进行感应耐压试验时，若试验频率为90Hz产生谐振,则全电压试验时间为120（90÷150）=72s。（）
答案
参考答案：错
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一台变压器用谐振法进行感应耐压试验时，若试验频率为90Hz产生谐振,则全电压试验时间为120（90÷150）=72s。（）
参考答案：错
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and secondary schools for the start of 2______ new school year. Filling classrooms from kindergarten to the 12th grade, they attend classes for an average of five hours a day, five days a week, until the beginning of the following summer. About 85% of American students 3______ public schools (schools supported by American taxpayers). The other 15% attend private schools, 4______ which their families choose to pay special attendance fees. Four out of five private schools in the United States are run by churches, synagogues (犹太教会堂) or other religious groups. In such schools, 5______ teachings are a part of the curriculum(课程), which also includes the traditional academic courses of reading, mathematics, history, geography and science. U.S. Department of Education makes every 6______ to educate an entire national population. The goal is-and has been since the early decades (a period of ten years) of the republic-to achieve universal literacy (able to read and write) and to 7______ individuals with the knowledge and skills necessary to promote both their own individual welfare (福利) as well as 8______ of the general public. Though this goal has not yet been achieved, it remains an ideal toward 9______ the American educational system is directed. The progress which has been 10______ is notable both for its scope (范围) and for the educational methods which have been developed in the process of achieving it. |