题目

实验操作中，常有“先”与“后”的分工，下列顺序不正确的是（） A . 电路连接好后，先检查，确认无误后再闭合开关 B . 用显微镜观察细胞时，先换到高倍镜，后对光 C . 用排水法收集完氧气，先把导管移离水面，后停止加热 D . 用托盘天平称量物质时，先加砝码，后移动游码 答案：B It is 6:00 am on the first day of the school year. In Cherrybrook Technology High School, mathematics teacher Eddie Woo is already at work.One of the first things before the first bell rings is to set up his tripod(三脚架) and iPad in the middle of the classroom. This technology is Mr. Woo's core tool of the trade. "I'm Mr. Woo. I record my lessons. I record all of them. In fact, I'm about to record this one," he explains to his new maths class.The unique approach to teaching mathematics has not gone unnoticed. Mr. Woo is arguably the most famous teacher in Australia - a maths teacher by day and an internet sensation(轰动) by night.He started posting videos online in 2012 for a student who was sick with cancer and missing a lot of school. Other students in the class then wanted to watch Mr. Woo's videos on his free YouTube channel and website, so he started sharing them across the country and beyond. Wootube now boasts more than 38,000 subscribersc用户 ) and has attracted almost 4 million views worldwide.Cherrybrook Technology High School principal Gary Johnson said Mr. Woo was helping address a standing shortage of maths teachers in Australia, and making maths popular again. “ He has an ability to simplify mathematics to a level where kids can really understand it," Mr. Johnson said.12-year-old student Emily Shakespear said Mr. Woo's teaching style made maths irresistible. "I don't want to say it, but he sucked me into maths," she said. Owen Potter, who attends high school in Cobar, agreed. "It's difficult to understand how someone in Sydney can influence thousands of people across the whole country," he said.Mr. Woo won the 2017 University of Sydney Young Alumni Award for Outstanding Achievement, and he was one of 12 Australian teachers honored at the Commonwealth Bank Teaching Awards.【1】Eddie Woo set up an iPad in the middle of the classroom with the purpose ofA.listening to musicB.playing a videoC.recording his classD.showing pictures【2】What can we infer from the statistics in the fourth paragraph?A.Mr. Woo's teaching videos online are very popular.B.Mr. Woo had made a lot of money by selling videos.C.Mr. Woo posted videos online helping many adults.D.Mr. Woo created his Wootube in 2012 in Sydney.【3】According to Gary Johnson, Mr. Woo's maths lessons areA.difficult to followB.easy to understandC.simple to handleD.challenging to learn【4】What is the main idea of the last paragraph?A.Mr. Woo is the most well-known maths teacher in Australia.B.Mr. Woo graduated from the University of Sydney with honors.C.Mr. Woo won the Commonwealth Bank Teaching Awards.D.Mr. Woo's contributions to teaching have been recognized.