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THE COYOTE 1 All North American canids have a doglike appearance characterized by a graceful body, long muzzle, erect ears, slender legs, and bushy tail. Most are social animals that travel and hunt in groups or pairs. After years of persecution by humans, the populations of most North American canids, especially wolves and foxes, have decreased greatly. The coyote, however, has thrived alongside humans, increasing in both numbers and range. 2 Its common name comes from coyotl, the term used by Mexico’s Nahuatl Indians, and its scientific name, canis latrans, means "barking dog." The coyote’s vocalizations are varied, but the most distinctive are given at dusk, dawn, or during the night and consist of a series of barks followed by a prolonged howl and ending with short, sharp yaps. This call keeps the band alert to the locations of its members. One voice usually prompts others to join in, resulting in the familiar chorus heard at night throughout the West. 3 The best runner among the canids, the coyote is able to leap fourteen feet and cruise normally at 25-30 miles per hour. It is a strong swimmer and does not hesitate to enter water after prey. In feeding, the coyote is an opportunist, eating rabbits, mice, ground squirrels, birds, snakes, insects, many kinds of fruit, and carrion--whatever is available. To catch larger prey, such as deer or antelope, the coyote may team up with one or two others, running in relays to tire prey or waiting in ambush while others chase prey toward it. Often a badger serves as involuntary supplier of smaller prey: while it digs for rodents at one end of their burrow, the coyote waits for any that may emerge from an escape hole at the other end. 4 Predators of the coyote once included the grizzly and black bears, the mountain lion, and the wolf, but their declining populations make them no longer a threat. Man is the major enemy, especially since coyote pelts have become increasingly valuable, yet the coyote population continues to grow, despite efforts at trapping, shooting, and poisoning the animals. Which animal sometimes unknowingly helps the coyote catch food
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RURAL CANADA 1 In the 1880s, over three-fourths of Canada’s population lived outside urban centers. One view of rural Canada at that time portrays it as a vast wasteland of isolated farm communities. However, a more accurate view shows that rural Canadians had access to considerable information. The postal service was efficient and inexpensive and connected rural Canadians with the outside world. Many farm families received at least one newspaper through the mail, usually within a day of publication. The daily newspapers of the period were more substantial than those of today, and many reproduced precise accounts of court trials and public events. Rural Canadians read magazines and books and held discussions about them at club meetings. 2 Rural Canadians were also able to get together socially. The local school served other functions besides providing formal education, and school districts were often the only sign of political organization in vast regions of the country. Every community valued its one- room schoolhouse as a meeting place, especially during the winter, when work on the farm was much lighter and people had more time for a variety of social and cultural events. People of all ages got together to sing and play musical instruments, perform skits, and play parlor games. 3 Between 1880 and 1920, there was a growing exodus from farms to the city, mainly because smaller farms could not afford to modernize their technology and were no longer able to support the entire family. However, most Canadians continued to hold rural values, and artists and writers romanticized the family farm. In the novel Anne of Green Gables (1908), Lucy Maud Montgomery wrote about a young woman who strove to reconcile the beauty and peace of the rural landscape with the need to leave it in order to fulfill her ambitions. For large numbers of young Canadians, growing up meant leaving the farm to find work in the city. According to the passage, the rural school provided all of the following services EXCEPT
I’m afraid we can’t have coffee; there’s ______ left.
EFFECTS OF IONIZING RADIATION 1 Everyone on Earth is continually exposed to small, relatively harmless amounts of ionizing radiation, known as background radiation, from natural sources such as soil and rock. However, other types of ionizing radiation--x-rays, ultraviolet radiation from the sun, and alpha, beta, and gamma radiation emitted by radioactive isotopes--have the potential to harm the human body. Ionizing radiation has enough energy to remove one or more electrons from the atoms it hits to form positively charged ions that can react with and damage living tissue. Most damage occurs in tissues with rapidly dividing cells, such as the bone marrow, where blood cells are made, and the digestive tract, whose lining must be constantly renewed. 2 Exposure to ionizing radiation can damage cells in two ways. The first is genetic damage, which alters genes and chromosomes. This can show up as a genetic defect in children or in later generations. The second type of damage is somatic, which causes victims direct harm in the form of bums, miscarriages, eye cataracts, some types of leukemia, or cancers of the bone, thyroid, breast, skin, and lung. Small doses of ionizing radiation over a long period of time cause less damage than the same total dosage given all at once. Exposure to a large dose of ionizing radiation over a short time can be fatal within a few minutes to a few months later. Which exposure to ionizing radiation causes the most serious damage to humans
Our company is ______ of other makers of spare parts for the airplane.
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