As coal mines became deeper, the problems of draining water, bringing in fresh air, and ________to the surface increased.
A.ore is transporting
B.to transport ore
C.how ore is transported
D.transporting ore

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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 42.
Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds - any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.
The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.
In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world's weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.
The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.
Which of the following is NOT given as an advantage of using biological agents over chemical herbicides?
A.They are safer for workers.                                
B.They are less likely to destroy desirable plants.
C.They are more easily available.                         
D.They do not have to be used as often.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.
For a century before the Erie Canal was built, there was much discussion among the general population of the Northeast as to the need for connecting the waterways of the Great Lakes with the Atlantic Ocean. A project of such monumental proportions was not going to be undertaken and completed without a supreme amount of effort.
The man who was instrumental in accomplishing the feat that was the Erie Canal was Dewitt Clinton. As early as 1812, he was in the nation's capital petitioning the federal government for financial assistance on the project, emphasizing what a boon to the economy of the country the canal would be; his efforts with the federal government, however, were not successful.
In 1816, Clinton asked the New York State Legislature for the funding for the canal, and this time he did succeed. A canal commission was instituted, and Clinton himself was made head of it. One year later, Clinton was elected governor of the state, and soon after, construction of the canal was started.
The canal took eight years to complete, and Clinton was on the first barge to travel the length of the canal, the Seneca Chief, which departed from Buffalo on October 26, 1825, and arrived in New York City on November 4. Because of the success of the Erie Canal, numerous other canals were built in other parts of the country.
The paragraph following the passage most probably discusses
A.the effect of the Erie Canal on the Buffalo area
B.Clinton's career as governor of New York
C.the century before the building of the Erie Canal
D.canals in different U.S locations