[单项选择]Although South Carolina's mineral resources are abundant, not all of them can be mined lucratively.


A. molten
B. plentiful
C. diverse
D. precious

[单项选择]Although South Carolina's mineral resources are abundant, not all of them can be mined lucratively.
A. molten
B. plentiful
C. diverse
D. precious

[单项选择]South Carolina's mineral resources are abundant, but not all of them can be lucratively mined.（）
A. profitably
B. safely
C. easily
D. extensively

[单项选择]

At this time the state of South Carolina was having hard times. Year after year the soil had been planted with the same crop. It was farmed by uneducated and careless slaves, and the planters knew little about soil conservation. Because the soil was beginning to wear out, crops were smaller.
The younger people were not satisfied to raise cotton on the poor soil of the old South. Many of them moved westward and started cotton plantation (大农场) in Alabama and Mississippi. Moreover, so much cotton had been shipped to factories in England and New England that they had as much cotton as they could use. This brought the price of cotton down. More and more slaves were needed to work on the new and larger plantations, and higher and higher prices were demanded for them. Planters found their expenses rising and their incomes from the sale of cotton reduced. Hard times had come to South Carolina.

Which of the following sentences can summarize the main idea of t
A. Hard times had come to South Carolina.
B. Planters found their expenses rising and their income reduced.
C. The soil was farmed by uneducated and careless slaves.
D. Year after year the soil of South Carolina had been planted with the same crop.

[单项选择]It can be inferred that had South Carolina not cast any electoral votes for Jefferson, the outcome of the 1796 election would have been a ______.
A. larger margin of victory for John Adams
B. victory for Thomas Jefferson
C. Federalist defeat in the Senate
D. victory for Thomas Pinckney

[单项选择]Although we all depend on the resources of nature for our survival, _______.


A. industrial products are replacing all our natural resources
B. it is only on islands that nature survives
C. we have forgotten what our original countryside looked like
D. we have allowed large areas of countryside to be spoilt by industrial development

[单项选择]Why does America confront the mineral resources problems


A. There are few mineral resources in America.
B. Excessive explorations and large consumption have exhausted many resources that are not renewable.
C. Geographic change and Climate effect.
D. Terrorist has burnt it over.

[单项选择]

Passage One
Magnesium is another mineral we now obtain by collecting huge volumes of ocean water and treating it with chemicals. Although originally it was derived only from brines or from the treatment of such magnesium-containing rocks as dolomite, of which whole mountain ranges are composed. In a cubic mile of sea water there are about four million tons of magnesium. Since the direct extraction method was developed about 1941, production has increased enormously. It was magnesium from sea that made possible the wartime growth of the aviation industry, for every, air plane made in the United States (and in most other countries as well) contains about haft a ton of magnesium metal. And it has innumerable uses in other industries where a lightweight metal is desired, besides its long-standing utility as an insulating material, and its use in printing inks, medicines, and toothpaste.

According to the passage, which of the following was a direct consequence of t
A. The development of insulation materials.
B. Increased airplane production.
C. Improved medical facilities.
D. The development of the cheap inks for printing.