题干

如图所示,为估算某河的宽度,在河对岸的边上选定一个目标点A,在近岸取点B,C,D,使得AB⊥BC,CD⊥BC,点E在BC上,并且点A,E,D在同一条直线上,若测得BE=20m,EC=10m,CD=20m,则河的宽度AB的长为(   )

A:60m

B:40m

C:30m

D:20m

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答案(点此获取答案解析)

B

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完形填空

    “I just think a year ago, at 54 years of age, I couldn't swim. I was terrified at the thought of going into the water. Now, I have just1my 200 meters. It feels like a2 and it is all thanks to Everyday Swim.”

    It's never too late to learn swimming. Angela King, 55, is a perfect3of it .For years, she had to4sting on the side of a pool watching her family splash(拍水)around. Then in August 2016, the family went to an attraction they hadn't5for 15 years. Angela thought, “All this time, I still can't6When I get back home tomorrow, I'm going to find out more about swimming7

    In the cold light of day, she felt a little8but her husband David searched the Inter-net for swimming classes. He found Everyday Swim at the local Hadleigh pool and9Angela to sign up. When she turned up for her first training, she says, “I felt a bit sick and10but this soon passed. The instructor11put me at ease, as did the other people in the class. They were all shapes and sizes12they were all feeling like me.”

    As the lessons13she learned to become more14in the water. At first, it was a simple15of learning she wasn't going to sink. Then during the third lesson, the Olympic gold medal winner Duncan Goodhew turned up to offer16“I couldn't believe it. He held my hand and we all held hands in a circle and splashed under the water. What he did made me believe that I could17it.

    When the 10 lessons for £100 offer finished at the pool, she18to sign up for lessons. In fact, from initially(开始) being19of the water, Angela was now becoming a regular swimmer and20some certificates along the way.