Read the following article and select the best answer. Article: One person can make a difference -- purchase your copy of For America and discover simple ways to improve your life, your country, even the world. But a simple and attractive way to cut energy costs, improve air quality, and ensure public health is to grow a garden in the sky. Each time a city building is set up, the grass in that spot and trees that once reached up to the sky are replaced by a layer of asphalt or a tar roof . The lost green space can have a very real effect on a city's air temperature, air quality, and energy costs. On a summer day in most American cities, a tar roof can feel like the inside of an oven . But what if we could replace the hot roof of each skyscraper or building in a city with grass or a garden? Whether it holds vegetable gardens, wildflowers, or grasses, a green roof can lower the temperature above a building by 60 degrees, which can reduce the building's energy costs and, if used more widely, could decrease a city's total energy costs, and improve air quality and public health. But that's not all -- green roofs are a great way to handle water management in urban areas by taking in much rainfall, provide shelters for urban wildlife, and actually extend the life of the roof itself. And green roofs also do something else: they beautify the city -- whether you're on the 3rd floor or the 30th. Now that's a brilliant achievement. The non-profit group Earth Pledge is promoting a Green Roofs Program. To learn more about a green roof, just click here: EarthPledge.com. Question: What do you think the article will talk about if the passage continues? - How to create a green roof. - The duty of the Earth Pledge. - The benefits of green roofs. - What to do with city pollution.
How to create a green roof.

Read the following article and select the best answer. Article: Mass transportation revised the social and economic fabric of the American city in three fundamental ways.It catalyzed physical expansion, it sorted out people and land uses, and it accelerated the inherent instability of urban life.By opening vast areas of unoccupied land for residential expansion, the omnibuses, horse railways, commuter trains, and electric trolleys pulled settled regions outward two to four times more distant form city centers than they were in the premodern era.In 1850, for example, the borders of Boston lay scarcely two miles from the old business district; by the turn of the century the radius extended ten miles.Now those who could afford it could live far removed from the old city center and still commute there for work, shopping, and entertainment.The new accessibility of land around the periphery of almost every major city sparked an explosion of real estate development and fueled what we now know as urban sprawl.Between 1890 and 1920, for example, some 250,000 new residential lots were recorded within the borders of Chicago, most of them located in outlying areas.Over the same period, another 550,000 were plotted outside the city limits but within the metropolitan area.Anxious to take advantage of the possibilities of commuting, real estate developers added 800,000 potential building sites to the Chicago region in just thirty years - lots that could have housed five to six million people. Of course, many were never occupied; there was always a huge surplus of subdivided, but vacant, land around Chicago and other cities.These excesses underscore a feature of residential expansion related to the growth of mass transportation: urban sprawl was essentially unplanned.It was carried out by thousands of small investors who paid little heed to coordinated land use or to future land users.Those who purchased and prepared land for residential purposes, particularly land near or outside city borders where transit lines and middle-class inhabitants were anticipated, did so to create demand... Question: Why does the author mention both Boston and Chicago? - To demonstrate positive and negative effects of growth. - To exemplify cities with and without mass transportation. - To show mass transportation changed many cities. - To contrast their rate of growth.
To show mass transportation changed many cities.

Read the following article and select the best answer. Article: It was a bitter cold evening in northern Virginia many years ago. The old man's beard was glazed by winter's frost while he waited for a ride across the river. The wait seemed endless. His body became numb and stiff from the frigid north wind. It was long before he heard the faint, steady rhythm of hooves along the frozen path. Anxiously watching several horsemen coming up, he let the first one pass by without any effort to get his attention, then another passed by, and another. Finally, the last rider drew near where the old man sat like a snow statue when old man caught his eyes and said, "Sir, would you mind giving an old man a ride to the other side?" Stopping his horse, the rider replied, "Sure! Jump aboard." Seeing the old man unable to lift his half-frozen body from the ground, the horseman got down to help him. The horseman took him not just across the river, but to his destination just a few miles away. As they approached the tiny but cozy cottage, the horseman's curiosity caused him to inquire, "Sir, I noticed you let several other riders pass by without making an effort to secure a ride. Then I came up and you immediately asked me for a ride. I am curious why, on such a bitter night, you would wait and ask the last rider. What if I had refused and left you here?" The old man looked the rider straight in the eyes and replied, "I reckon I know people pretty good. I looked into the eyes of the other riders and immediately found no concern for my situation. It would have been useless even to ask them for a ride. But when I looked into your eyes, your gentle spirit would welcome the opportunity to give me assistance in my time of need." Those heart-warming comments touched the horseman deeply. "I'm so grateful for what you have said," he told the old man. "May I never get too busy in my own affairs that I fail to respond to the needs of others with kindness and compassion." With that, Thomas Jefferson turned his horse around and made his way back to the White House. Question: What caused the last rider to stop and help the old man? - the old man's poor situation - kindness and sympathy - his own affairs - The old man's warm comments
kindness and sympathy