驾驶机动车在冰雪道路行驶时，最高速度不能超过多少？A、20公里/小时 B、30公里/

     The contemporary environmental movement is often said to have begun with the publication of Silent
Spring by the zoologist and biologist Rachel Carson (1907－1964). This landmark work, which took
Carson 4 years to complete, diligently detailed the relationship between animal death  and the use-now
understood as the abuse of manmade chemicals used as pesticides, especially DDT. One of the claims of
the book that she tried to demonstrate was that DDT had the effect of softening the eggshells of birds as
well as interfering with their reproduction, and that such effects would lead to their extinction if the use of
DDT were to continue. It would eventually create a springtime of silence when the songs of birds would
not be heard. Her studies also found DDT to be a cause of human cancers.
     Born in Springdale, Pennsylvania, Carson graduated from the Pennsylvania College for Women in
Pittsburgh (now Chatham College), where she majored in English until her junior year, when a course in
biology inspired her to switch to zoology as her field of concentration. She earned a master’s degree in
this area from Johns Hopkins University and became a biologist at the Bureau of Fisheries in 1936.
During this time, she wrote for various national magazines, and her first book, Under the SeaWind, was
published. Carson had concerns as early as 1945 about pesticides being used more and more by the
government. But her cautionary claims in Silent Spring were met with anger by the pesticide and chemical
industries. Her authority as a scientist was challenged, and it was held that her findings were just the roars
of a hysterical(歇斯底里的) woman. She was even accused of being a member of the Communist Party.
Some go so far as to say that she told a lie.
     But she is often celebrated as the founder of the contemporary U. S. environmental movement. Yet her work in Silent Spring, warning about the misuse of pesticides and other chemicals, has not as yet taken
firm hold. Americans likely use twice as much the volume of pesticides that they did at the time she
published her seminal work, and globally, their use is ever increasing. Powerful pesticides are sold over the
counter, and their use is so widespread that many environmentalists are fearful that chemical runoff into
streams and rivers is still polluting the animals that humans eat and the water that they drink. In short, while
the main purpose of Silent Spring was to warn the public of the dangers of the overuse of pesticides and
chemicals, nonetheless the public haven't refused such use. Isn't it time that we firmly said no to pesticides?