Do you know the difference between "sound" and "noise"
"Noise" is an unwanted sound, such as (67) produced by airplanes, traffic, or industrial machinery... You may probably (68) people saying, "There’s so much noise in the restaurant I can (69) hear you." or, "the noise is killing me." "Noise" is considered a form of pollution. Noise pollution is at its (70) in densely populated areas. It can cause hearing loss, stress, high blood pressure, sleep loss, distraction, and productivity loss.
"Sound" is (71) you hear. (72) , you hear the sound of people talking and singing, the sound of music, wind, breaking glasses... Sound travel sin sound wave at 1,100 feet an hour. Sounds are produced by objects that vibrate at a (73) that the ear can detect. This rate is called frequency and is measured (74) hertz, or vibrations per second.
Most hum ans can hear sounds between 20and 20,000 hertz, (75) dogs can hear high-pitched sounds up to 50,000 hertz. While high-frequency sounds tend to be more erous and more annoying to hearing than low-frequency sounds, most noise pollution damage is related to the intensity of the sound. Measured in decibels (分贝), noise intensity can (76) from zero, the (77) sound the human ear can detect, (78) over160 decibels. Conversation takes place at around40 decibels, a subway train is about 80 decibels, and a rock concert is from 80 to 100 decibels. The intensity of a nearby jet (79) is about 110decibels. The threshold (极限) for pain, tissue damage, and potential hearing loss in humans is120 decibels.
"Noise" is usually a loud sound but not always (80) . For passengers at an airport (81) want to see the planes taking off and landing, there may be a lot of sound, but not much noise. (82) , if you’re reading in the library and two people behind you are whispering, you feel that they’re talking noisily, 83 there isn’t much sound.
Solutions (84) noise pollution include adding insulation and sound-proofing to doors, walls, and ceilings; using ear protection (85) in industrial working areas; planting vegetation to absorb and screen out noise pollution; and zoning areas to maintain a separation between residential areas and zones of (86) noise.