Recently, online hike-sharing has become the new favorite in China. In major cities, bikes in, yellow, orange, blue, white and green, can be seen almost everywhere on the street. It seems that these bikes appeared suddenly, adding a new beautiful scenery to Chinese cities.

    Both the market and the public welcome online bike-sharing, but is it really a promising business? Well, it depends. After all, online bike-sharing platforms can never get away with huge operating cost and uncertain government policy.

    Some theorists might say that online bike-sharing platforms can earn a fortune simply through deposit. Since users will always need to rent bikes, their deposit will always be kept to online bike-sharing platforms.

    However，although online bike-sharing platforms may be able to use the deposit for other purposes at the primary stage, they will have to set up a special account, so that the deposit shall be used specially for its designated (指定的) purpose. As the market gets increasingly mature, they will have to do so whether to be responsible for users or in consideration of possible government regulations.

    Now that online hike-sharing platforms can，t make profit through deposit，how can they become profitable as fiercer market unfolds? Although Hu Weiwei, CEO of Mobike, stated in an article that she would take Mobike as charitable(慈善的) project if she failed, running a startup is absolutely different from managing a charity organization. After all , she has to pay back investors' billions of investment(投资).

    To make profit, online bike-sharing platforms might have toincrease rent fee for each trip, just as Didi did

    From this aspect, it might be a really good business. If we consider full screen ads fee, recommendation fee for business owners, etc. , its annual income might reach at least RMB 15 billion. If we consider the huge operation cost, including bike repairs，bikes' service life and labor cost, there might not be much net profit left. After all, offline operation cost has always been an unbearable burden for such internet plus mode-based startups.

根据短文内容，选择最佳答案，并将选定答案的字母标号填在题前括号内。

Make a five-minute film and win!

    Do you love the summer holidays but hate being bored? Then why don't you enter the Film Street Summer Shorts Competition by making a short film this summer with your family and friends?

What you have to do

    To enter the competition, you have to make a short film that around 5 minutes long (It can be shorter but not longer!) on a digital camera, or mobile phone.

Awards

    The best short film entered into our competition will be shown in Film Street's Cinema and you'll win a Cineworld Cinemas pass for yourself and there more for other members of your film crew. If you have a Cineworld Cinemas pass, you can watch as many films as you like for a year, for free, at any Cineworld Cinema!

Rules

.We can't show films that tell others about either your, or any other kids', name or address.

.We can't show films that hurt, harm or insult(侮辱） other people。

.We can't show films that have bad language.

Copyright Checklist

Getting permission to use someone else's work in your film can be expensive, so check your film to make sure that:

.Your film is original and you haven't copied someone else.

.There are no scenes of branding on shop signs, books, magazines or CDs.

.There are no scenes of someone else's artwork.

Address and Date

Post your finished film on tape, CD or DVD by Monday, October1st, 2007 to:

Unit 6,Third Floor, The Bond

180-182 Fazeley Street; Birmingham

    So what's stopping you? Start making your Film Street Summer Short now!

    Our brains work in complex and strange ways.There are some people who can calculate the day of the week for any given date in 40,000 years,but who cannot add two plus two.Others can perform complex classical piano pieces after hearing them once,but they cannot read or write.

    Dr.J.Langdon Down first described this condition in 1887.He called these people idiot savants.An idiot savant is a person who has significant mental impairment（损伤）,such as in autism（孤独症，自闭症）or retardation.At the same time,the person also exhibits some extraordinary skills,which are unusual for most people.The skills of the savant may vary from being exceptionally gifted in music or in mathematics,or having a photographic memory.

    One of the first descriptions of a human who could calculate quickly was written in 1789 by Dr.Benjamin Rush, an American doctor.His patient,Thomas Fuller,was brought to Virginia as a slave in 1724.It took Thomas only 90 seconds to work out that a man who has lived 70 years,17 days,and 12 hours has lived 2,210,500,800 seconds. Despite this ability,he died in 1790 without ever learning to read or write.

    Another idiot savant slave became famous as a pianist in the 1860s.Blind Tom had a vocabulary of only 100 words,but he played 5,000 musical pieces beautifully.

    In the excellent movie Rain Man,made in 1988 and available on video cassette,Dustin Hoffman plays an idiot savant who amazes his brother played by Tom Cruise,with his ability to perform complex calculations very rapidly.

    Today we more clearly recognize that the idiot savant is special because of brain impairment.Yet not all brain impairment leads to savant skills.Some studies have shown that people who have purposeful interruption of the left side of the brain can develop idiot savant skills.However few people wish to participate in such experiments.There are many excellent reasons for not undergoing unnecessary experimentation on one's brain.The term idiot savant is outdated and inappropriate.Virtually all savants have a high degree of intelligence and are thus not idiots.

    James Gross, a psychology professor at Stanford University, has a 13-year-old daughter who loves math and science. “It hasn't occurred to her yet that's unusual,” he says. “But I know in the next couple of years, it will.”

    She's already being pulled out of class to do advanced things with a couple of other kids, who are guys. And as someone who studies human emotion for a procession, Gross says, “I know as time goes on, she will feel increasingly lonely as a girl who's interested in math and science, and be at risk of narrowing her choices in life before finding out how far she could have gone.''

    Gross' concern clearly shows what has been a touchy subject in the world of science for a long time: Why are there still so few women in science, and how might that affect what we learn from research?

    Women now make up half the national workforce, earn more college and graduate degrees than men, and by some estimates represent the largest single economic force in the world. Yet the gender gap in science persists, to a greater degree than in other professions, particularly in high-end, math-intensive fields such as computer science and engineering.

    According to US Census Bureau statistics, women in fields commonly referred to as STEM (science, technology, engineering, mathematics) made up 7 percent of that workforce in 1970, a figure that had jumped to 23 percent by 1990. But the rise essentially stopped there. Two decades later, in 2011, women made up 26 percent of the science workforce.

    Scientists from the University of East Anglia have identified four new man-made gases that are contributing to the damage to the ozone(臭氧) layer. Two of the gases are accumulating at a rate that is causing concern among researchers.

    Worries over the growing ozone hole have seen the production of chlorofluorocarbon (CFC) gases restricted since the mid 1980s. But the precise origin of these new, similar substances remains a mystery.

    Lying in the atmosphere, the ozone layer plays a critical role in blocking harmful UV rays, which cause cancers in humans and reproductive problems in animals.

    Scientists from the British Antarctic Survey were the first to discover a huge “hole” in the ozone over Antarctica in 1985. The evidence quickly pointed to CFC gases, which were invented in the 1920s, and were widely used in refrigeration. Extraordinarily, global action was rapidly agreed to deal with CFCs and the Montreal Protocol to limit these substances came into being in 1987. A total global ban on production came into force in 2010.

    Now, the newly discovered four new gases can destroy ozone and are getting into the atmosphere from as yet unidentified sources. Three of the gases are CFCs and one is a hydrochlorofluorocarbon (HCFC), which can also damage ozone.

    The research has shown that four gases were not around in the atmosphere at all until the 1960s, which suggests they are man-made. The scientists discovered the gases by analyzing polar snow pack. Air from this snow is a natural archive of what was in the atmosphere up to 100 years ago. There searchers also looked at modern air samples, collected at remote Cape Grim in Tasmania.

    They estimate that about 74,000 tonnes of these gases have been released into the atmosphere. Two of the gases are accumulating at significant rates. However, they don't know where the new gases are being released from and this should be investigated. Possible sources include chemicals for insecticide (杀虫剂)production and solvents (溶液) for cleaning electronic components. The three CFCs are being destroyed very slowly in :the atmosphere—so even if emissions (散发)were to stop immediately, they will still be around for many decades to come.

    Of the four species identified, CFC-113a seems the most worrying as there is a very small but growing emission source somewhere, maybe from agricultural insecticides. We should find it and take it out of production.

 The recent opening of a new exhibition building at the Sanxingdui Museum, in Guanghan, in Sichuan province, made the place {#blank#}1{#/blank#} instant tourist hot spot. The bronze heads, golden masks, holy trees and various statues reveal the {#blank#}2{#/blank#} ( mystery) faces of a culture dating back more than 3,000 years.

 For those who cannot make it to Guanghan, where the extensive site of Sanxingdui is located, an immersive exhibition equipped with digital technology, {#blank#}3{#/blank#} ( title) Hello Sanxingdui, {#blank#}4{#/blank#}( offer) an alternative means to be awed by the magnificence of this Bronze Age culture. It is running at the Longfu Art Museum in Beijing until Feb 29.

 It provides a time- travel experience for both an educational and artistic appeal. The journey begins {#blank#}5{#/blank#} a brief timeline of texts, photos and videos, showing how Sanxingdui was first discovered in the 1920s,{#blank#}6{#/blank#} objects were found by farmers digging an irrigation ditch(灌溉沟渠); and it highlights the important moments in the past century's continued archaeological efforts, to reveal the myths surrounding Sanxingdui and the secrets yet {#blank#}7{#/blank#} ( uncover).

 On show {#blank#}8{#/blank#} ( be) life- size reproduction s of dozens of astonishing artifacts, supervised by Sanxingdui Museum, such as 2.6- meter bronze statues, 3.8- meter- wide bronze masks and" the holy tree" standing nearly 4 meters.

 Images of these objects found at Sanxingdui and their {#blank#}9{#/blank#} ( pattern) have been digitalized, animated and projected on screens, leading the audience into the ancient kingdom of Shu, a {#blank#}10{#/blank#}( civilize) that thrived for centuries in the southwest during the Zhou Dynasty, and disappeared suddenly, leaving many myths and legends.