单选题According to the passage, one thing eusocial insects can do is rapidly switch from

单选题Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points. In early March 1997, a farmer from Hong Kong died of avian flu which later came to official attention. ● ● ● Answer ChoicesA. As one of the most changeable viruses known to man, flu can change the cells of humans so as to infect humans after humans have been ill with one strain. Humans are immune to the flu their bodies have experienced before.B. The contagious chain effect of H5N1 from the virus itself to an animal which passes it on to humans who infect their peers in a simple cough or sneeze can spark a world outbreak.C. It was found by the Agriculture and Fisheries Department laboratory that H5N1, a kind of virus was the prime culprit in this catastrophe.D. After H5 suddenly appeared in Hong Kong, flu experts were worried that this flu, which had already been very likely to cause death of humans, might learn to move between them toe.E. In order to cure the infection by Spanish flu, three measures need be adopted by all nations, which are better surveillance, more vaccines and flu shots, and a strong pandemic plan.F. Most countries don't start tracking avian flu until after an epidemic kills their chickens. The United States dramatically increased its monitoring after a deadly outbreak in Pennsylvania in the early 1980s.

单选题According to the passage, how many of the farmers who settled land under the Timber Culture Act of 1873 received final title to the property?

单选题The college that became Harvard University, the oldest institution of higher learning at the United States, was founded in Cambridge, Massachusetts, in 1636.

单选题The (earliest successful) sewing (machines) were powered by (turn) a (hand crank).

单选题What regular service did The Associated Press and United Press International begin to offer subscribing newspapers in the 1930's?

单选题The word "eager" in line 29 is closest in meaning to

单选题Ice crystals in a glacier tends to melt and recrystallize within a brief moment of travel on a downhill glide.

单选题The passage mainly discusses ancient Greek pottery and its

单选题In the period between 1918 and 1939, various political, economic, and geographic(factors combined) in (determine) the extent (to which) a country (developed) civil aviation.

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单选题The word "laborious" in line 8 is closest in meaning to

单选题Humans, ________, interact through communicative behavior by means of signs or symbols used conventionally.

单选题In general, novels are thought of extended works of prose fiction depicting the inner and outer lives of their characters.

单选题The author mentions that published music is not considered to be folk music because

单选题Whatarethespeakersmainlydiscussing?

单选题Kangaroos use (their) long and (powerful) tails (for) balance themselves (when sitting. upright or jumping. A. their B. powerful C. for D. when sitting

单选题Listentopartofalectureinasportsengineeringclass.Nowgetreadytoanswerthequestions.Youmayuseyournotestohelpyouanswer.Listenagaintopartofthelecture.Thenanswerthequestion.

单选题The sunflower, the official state flower of Kansas, and is widespread in the prairies of the western United States.

单选题A situation in which an economic market is dominated by a ____ is known as a monopoly.