阅读理解。
Sixteen-year-old Karlos Dearmans's future is looking much brighter than be might have imagined.
"I've always been into bikes, but never thought I'd end up working with them," he says. "This scheme
has changed my life."
Karlos is learning to refurbish (翻新) old bicycles in the workshop of ReCycle Bikes, a local community
(社区) charity in Sheffied, which has a contract with the city council to provide training opportunities for
young people aged 14 to 16, particularly those dropping out of school.
"It's about engaging youngsters with education and you thtraining by teaching them work and life skills,"
explains Des Pearce, workshop training manager. "These young people have so much potential, but often
don't realize it."
Established in 2001, ReCycle Bikes repairs bicycles donated by the public, which, once restored, are
sold for ￡20. Abandoned bikes supplied by the council ensure a steady flow of bikes, but a recently
formed partnership with Sheffield University should improve further the prospects of the young mechanics.
"The student population presents a large and ready market," says Pearce. "So we approached the
university last year and offered to host bike sales on the campus. They thought it was a great idea, and
agreed to supplement our council funding. This means we can train youngsters to repair extra 500 bikes
over three years."
Having set up ReCycle Bikes on his own, Pearce now has the staff and resources to track the career
development of those who have passed through his workshop. "However, in the past we depended on
the evidence of personal accounts from the schools because of lack of human and material resources,"
he says.
That most of the teenagers enjoy the work is, according to Pearce, easily explained. "Most kids have
ridden a bike and know how to oil a chain or mend a puncture. As low-cost transport, cycling gives the
young and old a sense of freedom and independence, and the impact on their well-being is immense. Add
to that a growing concern for the environment, and it's no surprise that bike sales are on the increase."
1. What do we know about ReCycle Bikes?
A. It is a popular brand of bikes which are sold in Sheffield.
B. It is a local community charity that provides training opportunities for reenagers.
C. It is a contract signed between a local community charity and the city council.
D. It is a training program offered by the city council to those excluded from school.
2. How did ReCycle Bikes run at the beginning?
A. By repairing bicycles donated by the public and selling them.
B. By donations from the public and Sheffield University.
C. By selling bicycles supplied by the city council.
D. By tuition fees from kids aged between 14 and 16.
3. ReCycle Bikes has formed a partnership with Sheffield University because ____.
A. students at Sheffield University assure a large and ready market
B. Sheffield University offers many mechanical teachers to ReCycle Bikes
C. heffield University donates a lot of money to ReCycle Bikes
D. teenagers at ReCycle Bikes can study at Sheffield University
4. ReCycle Bikes depended on information from the schools in the past because ____.
A. the schools could give accurate information to improve its service
B. students disliked telling the truth when asked about their personal ideas
C. ReCycle Bikes didn't have the ability to track students' career development
D. most of the training organizations did it this way at that moment
，方向如图所示．把半球面分为表面积相等的上、下两部分，如图甲所示，上、下两部分电荷在球心O处产生电场的场强大小分别为El、E2；把半球面分为表面积相等的左、右两部分，如图乙所示，左、右两部分电荷在球心O处产生电场的场强大小分别为E3、E4．则（ ）
，且电荷只分布球的表面，对于图甲，虽表面积相同，但由于间距的不同，则上、下两部分电荷在球心O处产生电场的场强大小关系为El＞E2；因电荷Q在球心O处产生物的场强大小
，则
；对于图乙，半球面分为表面积相等的左、右两部分，是由于左右两个半个球壳在同一点产生的场强大小相等，则根据电场的叠加可知：左侧部分在O点产生的场强与右侧电荷在O点产生的场强大小相等，即E3=E4 ．由于方向不共线，由合成法则可知，
；故A正确，BCD错误．