WHAT IS THIS PASSAGE MAINLY CONCERNED WITH
10. What is this passage mainly concerned with?
A. technology
B. a history of the Internet
C. computer users
D. a successful business
III. Read the following passage and circle the letter (A, B, C or D) to indicate the correct answer to each
of the following questions. (2.0 points)
No one can calculate the quantity of solid waste that has been dumped in the world’s oceans, but the
total certainly exceeds many millions of tons. For example, from 1880 to 1895, 75 percent of the solid waste
from New York City was dumped untreated into the Atlantic Ocean. Although it is now prohibited by law,
the dumping of solid waste, including wastewater sludge, industrial waste, and high - level radioactive waste
were common in the United States until 1970. Cruise ships and huge floating fishing factories still regularly
dispose of their solid waste products directly into the ocean.
The earth naturally recycles water and refreshes the land in what is called the hydrological cycle. The
hydrological cycle not only renews the supply of water, but cleans it as well. The process begins as heat from
the sun causes sea water, 97 percent of the earth’s total water reserve, to evaporate and form clouds. Because
water evaporates at lower temperatures than most pollutants, the water vapor that rises from the seas is
relatively pure and free of the
contaminants, which are left behind. Next, water returns to us as rain,
which
drains into streams and rivers and rushes toward the sea.
Chemicals, petroleum products, and other dangerous substances such as radioactive materials remain
in the ocean, polluting it permanently. The polluted ocean water kills fish or makes them dangerous to eat,
posing health problems for those who consume them. It kills the tiny sea creatures that are the source of food
for larger fish, sharks, and whales. It also spoils a source of great beauty and pleasure when some solid waste
is thrown onto beaches during storms. Discharged petroleum products are frequently found on beaches and
they not only ruin the beach, the petroleum residue kills hundreds of shore birds. Nonpoint pollutants are
dumped into lakes, rivers, and streams that may be far away from any ocean. However, these pollutants flow,
eventually, into the oceans. They can come from a variety of sources, from road salt to agricultural pesticides.
One source of nonpoint pollution is runoff from farming, including fertilizers, manure, and pesticides.
Another source is industrial runoff, including heavy metals, phosphorous, and many other chemicals. Urban
runoff (oils, salts, various chemicals) and atmospheric fallout of airborne pollution are other sources of
nonpoint pollutants that reach the oceans. This includes water and waste from sinks, toilets, washing
machines and bathtubs. The problem with this type of waste is that it provides massive amounts of nutrients
for water plants such as algae, so that they grow rapidly. This sudden growth causes concentration or algae
blooms, which use up the oxygen in the water. As the oxygen level of the water declines, many organisms
suffer and die, and the ocean ecosystem is radically altered. This can be prevented by the installation of waste
treatment plants that prevent waste from entering the sea, but such facilities do not exist in many poorer
countries.