How Long Did the Pony Express Exist?
There are many stories about the men who carried mail across America by the Pony Express, but the Pony Express really didn’t last very long. It began in 1860, carrying mail between Missouri and California by horseback. Stations were set up along the route, about 15 miles apart, where fresh horses were kept for the riders. Each r
A. 61 years.B. 6 months. C. One year.D. 18 months. 68. According to the passage, the Pony Express riders are____. A. orphansB. well over 18 C. skillful cart-drivers D. courageous and brave young men TEXT B Blind people usually possess one advantage over other people who can see: their sense of hearing is far more acute. Sounds which most others would miss can carry a great deal of information to a sightless person. For instance, teams of blind children can enjoy fast-moving games of soccer with a bell inside the ball and a new hand-held ultrasonic device to guide them. And that sound-location system could help to build up an even more complete sound picture of a blind persons surroundings. Bats, whose sight is poor, use a sound-location system to help them avoid obstacles in the dark. They send out pulses of sound waves, pitched at 50,000 cycles per second, far above the limits of the human ear, which can hear sounds up to frequencies of about 20,000 cycles per second. As the echoes bo
