题干

甲、乙两名同学在参加今年体育中考前各作了5次立定跳远测试,两人的平均成绩相同,其中甲的成绩的方差是0.005,乙的成绩如下:2.20m,2.23m,2.23m,2.24m,2.23m,则下列结论中正确的是(  )

A:甲的成绩更稳定

B:乙的成绩更稳定

C:甲乙的成绩一样稳定

D:不能确定谁的成绩更稳定

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答案(点此获取答案解析)

B

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阅读理解

    Winter sports tend to be more dangerous than summer sports — they take place mostly outside at the mercy of ice or snow, involving (牵涉) metal edges, extreme speeds and crashes. Skeleton (俯视冰梭), however, stands apart as one of the most difficult and least accessible of all the winter sports. Adam Edelman, Israel's first Olympic skeleton athlete, would like to change that.

    Edelman was the 10th athlete named to the 2018 Israeli Olympic Team. Qualifying for the Olympics in any sport is impressive. But it's more impressive if you qualify for the Olympics after only four years in the sport — and without a coach.

    Edelman was first introduced to skeleton watching the game on television in late 2013. Sports have always been a part of his life. He grew up playing football and was a goalkeeper on the Massachusetts Institute of Technology football team. Ready for a new challenge, he set his sights on the Olympics.

Without a coach, Edelman learned to drive by watching endless hours of YouTube videos and taking more runs than anybody else on the track. “When everybody else would take three runs per day, I would take six to eight.” he recalled.

    Succeeding in skeleton takes a large amount of athletic ability and technical skill, but there's one more element (因素) required, one that can't be taught. “These tracks but built in the middle of nowhere, and it's gray and cold. You haven't seen your family in seven months and you really just want to give up. To continue, it takes tenacity.” Edelman said.

    Edelman is already looking beyond Pyeongchang. The 2022 Olympics could be in his future, but whether he continues to compete or not, he promises to stay in Israeli sports as long as possible-as instructor or as a coach.