Questions 46 to 50 are based on the following passage:

　　The lives of very few Newark residents are untouched by violence: New Jersey’s biggest city has seen it all. Yet the murder of three young people, who were forced to kneel before being shot in the back of the head in a school playground on August 4th, has shaken the city. A fourth, who survived, was stabbed and shot in the face. The four victims were by all accounts good kids, all enrolled in college, all with a future. But the cruel murder, it seems, has at last forced Newarkers to say they have had enough.

　　Grassroots organizations, like Stop Shooting, have been flooded with offers of help and support since the killings. Yusef Ismail, its co-founder, says the group has been going door-to-door asking people to sign a pledge of non-violence. They hope to get 50,000 to promise to “stop shooting, start thinking, and keep living.” The Newark Community Foundation, which was launched last month, announced on August 14th that it will help pay for Community Eye, a surveillance(监视) system tailored towards gun crime.

　　Cory Booker who became mayor 13 months ago with a mission to revitalize the city , believes the surveillance program will be the largest camera and audio network in any American city. More than 30 cameras were installed earlier this summer and a further 50 will be installed soon in a seven-square mile area where 80% of the city’s recent shootings have occurred. And more cameras are planned.

　　When a gunshot is detected, the surveillance camera zooms in on that spot. Similar technology in Chicago has increased arrests and decreased shootings. Mr. Booker plans to announce a comprehensive gun strategy later this week.

　　Mr. Booker, as well as church leaders and others, believes(or hopes)that after the murder the city will no longer stand by in coldness. For generations, Newark has been paralyzed by poverty ----almost one in three people lives below the poverty line----and growing indifference to crime.

　　Some are skeptical .Steve Malanga of the conservative Manhattan Institute notes that Newark has deep social problems: over 60% of children are in homes without fathers. The school system, taken over by the state in 1995, is a mess. But there is also some cause for hope. Since Mr. Booker was elected, there has been a rise in investment and re-zoning for development. Only around 7% of nearby Newark airport workers used to come from Newark; now, a year, the figure is 30%.Mr Booker has launched a New York-style war on crime. So far this year, crime has fallen 11% and shootings are down 30 %( through the murder rate looks likely to match last year’s high).