Passage Three: Questions are based on the following passage.

If you wanted to question whether global warming is indeed upon us, last week was not the time to do it. Two weeks before the official beginning of summer, a heat wave baked the eastern third of the U.S. and Canada, driving temperatures high into the 90s and even 100s. At the same time, a flurry of scientific papers was released that seemed to explain all the late-spring suffering. In one study, French researchers reported that heat-trapping greenhouse gases are at their highest levels in 420,000 years. In another, U.S. scientists found that 57species of butterfly may be altering their migratory patterns in response to changing heat patterns.

In light of all this, a sweltering public must have been convinced at last that it’s time to do something to cool off the overheated planet, right? Wrong. Even as the temperature was climbing, a new survey by the American Geophysical Union found that Americans are less concerned than ever about combating global warming. “The more we talk about warming,”says the study’s director,John Immerwahr, “the [more the] public’s concern goes down.”

Such an environmental disconnect may not be much of a mystery. Environmentalists complain that over the past two years industry groups have launched a coordinated advertising campaign to torpedo the 1997 Kyoto treaty, which requires industrial nations to reduce greenhouse emissions. More than $13 million has been spent on ads to block ratification of the treaty by the U.S. Senate. “The purpose of the ads was to convince most Americans that there isn't a problem or that it’s too expensive to fix,” says National Environmental Trust spokesman Peter Kelly.

Environmentalists also criticize the U.S. Presidents for what they believe is their failure to press the issue. For example, in the year of 1997, President Clinton moved for Kyoto treaty changes that environmental groups see as industry-pleasing loopholes. Says Daniel Weiss, the Sierra Club’s political director: “Timid leaders communicate hopelessness.” And hopelessness breeds indifference. If such popular so-whating persists, Immerwahr warns, the public may begin grasping at phony solutions to global warming. At the end of last week, some people took comfort from the report of a vast haze of pollutants that collects over the Indian Ocean in the winter, but that researchers only recently studied. Filthy as the cloud is, it does deflect solar radiation, and that could lead to cooling. But scientists warn that we cannot simply pollute our way out of global warming. The soot drops from the hazy atmosphere in weeks, whereas greenhouse gases remain for centuries.

The way out of this gridlock, environmentalists say, is to show it's possible to reduce greenhouse gases without sinking the economy. Solutions include cleaner cars and better wind-and solar-power technologies. Says Greg Wetstone, program director for the Natural Resources Defense Council: “When these kinds of options become available, people will feel less hopeless.” Of course, it's also possible that only when people feel less hopeless will they press their leaders to make the solutions available.

According to the author, global warming is ________.

Speaking of global warming, American public is ________.

The public’s reaction to global warming is mainly a result of ________.

Which of the following is NOT mentioned in the passage?

It can be inferred from the passage that ________.