Nokea
Have you ever wondered why the whistle of a traveling, distant locomotive predicts its approach several yards before anyone actually sees it? Or why an oncoming ambulance's screaming siren is heard momentarily several feet before the ambulance comes into full view, before it passes you, and why its siren is still heard faintly well after the ambulance is out of sight?
What you are witnessing is a scientific phenomenon known as the Doppler Effect. What takes place is truly remarkable. In both of these instances, when the train or ambulance moves toward the sound waves in front of it, the sound waves are pulled closer together and have a higher frequency. In either instance, the listener positioned in front of the moving object hears a higher pitch. The ambulance and locomotive are progressively moving away from the sound waves behind them, causing the waves to be farther apart and to have a lower frequency. These fast-approaching modes of transportation distance themselves past the listener, who hears a lower pitch.
What is the main idea of the passage?
- A. Trains and ambulances emit distinctive sounds.
- B. Low-frequency waves result in high-pitched sounds.
- C. High-frequency waves lead to low-pitched sounds.
- D. The Doppler Effect explains why sound is initially heard more strongly and then faintly after a moving object has passed.
Correct Answer: D
Rationale: The main idea of the passage is to explain the phenomenon of the Doppler Effect, which is demonstrated by the sound changes produced by a moving object like a train or an ambulance. As these objects approach a listener, the sound waves are compressed, resulting in a higher frequency and pitch. Conversely, as they move away, the waves are stretched, leading to a lower frequency and pitch. This effect is what causes the sound to be initially loud and then fade away after the object passes, as observed with the ambulance and locomotive.
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Foodborne illnesses are contracted by eating food or drinking beverages contaminated with bacteria, parasites, or viruses. Harmful chemicals can also cause foodborne illnesses if they have contaminated food during harvesting or processing. Foodborne illnesses can cause symptoms ranging from upset stomach to diarrhea, fever, vomiting, abdominal cramps, and dehydration. Most foodborne infections are undiagnosed and unreported, though the Centers for Disease Control and Prevention estimates that every year about 76 million people in the United States become ill from pathogens in food. About 5,000 of these people die. Harmful bacteria are the most common cause of foodborne illness. Some bacteria may be present at the point of purchase. Raw foods are the most common source of foodborne illnesses because they are not sterile; examples include raw meat and poultry contaminated during slaughter. Seafood may become contaminated during harvest or processing. One in 10,000 eggs may be contaminated with Salmonella inside the shell. Produce, such as spinach, lettuce, tomatoes, sprouts, and melons, can become contaminated with Salmonella, Shigella, or Escherichia coli (E. coli). Contamination can occur during growing, harvesting, processing, storing, shipping, or final preparation. Sources of produce contamination vary, as these foods are grown in soil and can become contaminated during growth, processing, or distribution. Contamination may also occur during food preparation in a restaurant or a home kitchen. The most common form of contamination from handled foods is the calicivirus, also called the Norwalk-like virus. When food is cooked and left out for more than two hours at room temperature, bacteria can multiply quickly. Most bacteria don’t produce an odor or change in color or texture, so they can be impossible to detect. Freezing food slows or stops bacteria’s growth, but does not destroy the bacteria. The microbes can become reactivated when the food is thawed. Refrigeration also can slow the growth of some bacteria. Thorough cooking is required to destroy the bacteria.
What does the term 'sterile' mean as used in the second paragraph?
- A. free of bacteria
- B. healthy
- C. delicious
- D. impotent
Correct Answer: A
Rationale: In the context of the second paragraph, 'sterile' means 'free of bacteria.' Raw foods like meat and poultry are highlighted as common sources of foodborne illnesses because they are not sterile, indicating that they may contain harmful bacteria. Therefore, the term 'sterile' in this context refers to being free of bacteria, which corresponds with choice A.
Nurseries: If you thought nurseries were just for babies, well, think again! Being special kinds of farms, nurseries are used to raise plants in mass quantities. Plants, trees, and shrubs are typically grown in nurseries and then sold to farmers and gardeners to plant in homes, businesses, and farms. Most nurseries are found in the more rural parts of the country because much land is required to have a viable nursery. If a nursery sells plants to others, it must obtain a special permit from the local city or county, which keeps the competition fair and does not saturate the market with a large number of nurseries selling similar products.
Also on the grounds of nurseries are greenhouses which are made of glass or plastic panes that protect the plants from weather elements that may harm them and cause them not to grow and develop. The glass panels in greenhouses allow for sunlight to enter and moisture to be trapped inside. This creates a tropical environment which allows orchids and poinsettias to grow. It ensures that vegetables and fruits will grow large, which makes them valuable to farmers.
Nurseries are
- A. Places to care for infants.
- B. Special kinds of farms used to raise plants.
- C. Found only in rural areas.
- D. Used to grow vegetables and fruits.
Correct Answer: B
Rationale: The correct answer is B: Special kinds of farms used to raise plants. The passage explicitly states that nurseries are farms used to raise plants in mass quantities such as plants, trees, and shrubs. This is reinforced by the description of nurseries being special kinds of farms and selling plants to farmers and gardeners.
Choice A is incorrect because nurseries are not places to care for infants, as mentioned in the passage. Choice C is incorrect as nurseries are found in rural parts but not exclusively. Choice D is incorrect as the passage mentions that vegetables and fruits are grown in greenhouses on the grounds of nurseries, but the primary purpose of nurseries is to raise plants in mass quantities.
Linking San Francisco to Marin County in California, the Golden Gate Bridge is one of the most famous bridges in the world. The bridge crosses over a narrow strait which connects the Pacific Ocean to San Francisco Bay. Prior to the bridge, people traveled by ferry boat across the strait.
Although most people thought a bridge was necessary to expedite travel, some residents of the
bay area felt the risk of building the bridge was too great. Joseph Strauss believed that nothing was impossible, and dreams would never come to fruition if risks weren't taken. So, he decided to gather the best and brightest builders, architects, and workers to embark on the challenge of
building a bridge across the Golden Gate Strait. With safety nets in place, the construction began in 1937. Building the anchorages first, the
builders then move on to the towers on each end, and then to the three-foot thick cables to support the suspension bridge. Lastly, workers labored to complete the roadway which became
the most dangerous and treacherous part of the entire task. The builders had to keep the bridge
balance, so it wouldn't fall into the bay.
Today, over sixty-five years later, the bridge remains a life-line for the people of the San Francisco Bay Area.
In the passage the word embark means to:
- A. Put or go on board a ship
- B. Remove the covering from a tree
- C. Speak harshly to others
- D. Being an undertaking
Correct Answer: D
Rationale: In the context provided in the passage, the word 'embark' is used to describe the action taken by Joseph Strauss to start on the challenge of building a bridge across the Golden Gate Strait. 'Embark' in this context means to undertake or start an important or challenging task. Therefore, the correct answer is D: 'Being an undertaking.' This choice aligns with the idea of starting a challenging project, as seen in the passage.
Searching for medical information can be confusing, especially for first-timers. However, if you are patient and stick to it, you can find a wealth of information. Your community library is a good place to start your search for medical information. Before going to the library, you may find it helpful to make a list of topics you want information about and questions you have. Your list of topics and questions will make it easier for the librarian to direct you to the best resources. Many community libraries have a collection of basic medical references. These references may include medical dictionaries or encyclopedias, drug information handbooks, basic medical and nursing textbooks, and directories of physicians and medical specialists (listings of doctors). You may also find magazine articles on a certain topic. Look in the Reader’s Guide to Periodical Literature for articles on health and medicine from consumer magazines. Infotrac, a CD-ROM computer database available at libraries or on the Web, indexes hundreds of popular magazines and newspapers, as well as medical journals such as the Journal of the American Medical Association and New England Journal of Medicine. Your library may also carry searchable computer databases of medical journal articles, including MEDLINE/PubMed or the Cumulative Index to Nursing and Allied Health Literature. Many of the databases or indexes have abstracts that provide a summary of each journal article. Although most community libraries don’t have a large collection of medical and nursing journals, your librarian may be able to get copies of the articles you want. Interlibrary loans allow your librarian to request a copy of an article from a library that carries that particular medical journal. Your library may charge a fee for this service. Articles published in medical journals can be technical, but they may be the most current source of information on medical topics.
What is the meaning of the word 'technical' as it is used in the fourth paragraph?
- A. requiring expert knowledge
- B. incomplete
- C. foreign
- D. plagiarized
Correct Answer: A
Rationale: The word 'technical' in the fourth paragraph refers to information that is complex and requires expert knowledge to understand. Medical journal articles are often technical in nature, containing specialized terminology and detailed research findings that may be challenging for the general public to interpret. Therefore, choice A, 'requiring expert knowledge,' is the correct meaning of 'technical' in this context.
A BIT ABOUT BICYCLES
Today, bicycles are so common that it's hard to believe they haven't always been around. But two hundred years ago, bicycles didn't even exist, and the first bicycle, invented in Germany in 1818, was nothing like our bicycles today. It was made of wood and didn't even have pedals. Since then, however, numerous innovations and improvements in design have made the bicycle one of the most popular means of recreation and transportation around the world. In 1839, Kirkpatrick Macmillan, a Scottish blacksmith, dramatically improved upon the original bicycle design. Macmillan's machine had tires with iron rims to keep them from getting worn down. He also used foot-operated cranks like pedals, so his bicycle could be ridden at a quick pace. It didn't look much like a modern bicycle, though, because its back wheel was substantially larger than its front wheel. In 1861, the French Michaux brothers took the evolution of the bicycle a step further by inventing an improved crank mechanism. Ten years later, James Starley, an English inventor, revolutionized bicycle design. He made the front wheel many times larger than the back wheel, put a gear on the pedals to make the bicycle more efficient, and lightened the wheels by using wire spokes. Although this bicycle was much lighter and less tiring to ride, it was still clumsy, extremely top heavy, and ridden mostly for entertainment. It wasn't until 1874 that the first truly modern bicycle appeared on the scene. (14) Invented by another Englishman, H.J. Lawson, the "safety bicycle" would look familiar to today's cyclists. This bicycle had equal-sized wheels, which made it less prone to toppling over. Lawson also attached a chain to the pedals to drive the rear wheel. With these improvements, the bicycle became extremely popular and useful for transportation. Today they are built, used, and enjoyed all over the world.
After reading this article, the reader learned that:
- A. Bicycles have changed significantly over the years.
- B. Modern bicycles are used for both recreation and transportation.
- C. Bicycling is gaining in popularity all over the world.
- D. Bicycles are not a recent invention and have a long history.
Correct Answer: C
Rationale: The correct answer is C: 'Bicycling is gaining in popularity all over the world.' The passage discusses the evolution of bicycles from their early designs to modern ones, highlighting how they have become one of the most popular means of recreation and transportation globally. The information provided in the passage indicates that bicycles have undergone significant changes and improvements over the years, making them more popular and widely used. Therefore, the statement that bicycling is gaining popularity worldwide is supported by the passage.