植物异花传粉依传粉媒介的不同，可分2大类，即风媒传粉和虫媒传粉。( )

监测冰岛火山灰的扩散面积和浓度变化所利用的技术手段主要是（ ）

C

GUATEMALA CITY （Reuters） – A fish that lives in mangrove swamps（红树沼泽）across the Americas can live out of water for months at a time, similar to how animals adapted（适应）to land millions of years ago, a new study shows.

The Magrove Rivulus, a type of small killifish, lives in small pools of water in a certain type of empty nut or even old beer cans in the mangrove swamps of Belize, the United States and Brazil. When their living place dries up, they live on the land in logs（圆木），said Scott Taylor, a researcher at the Brevard Endangered Lands Program in Florida.

The fish, whose scientific name is Rivulus marmoratus, can grow as large as three inches. They group together in logs and breathe air through their skin until they can find water again.

The new scientific discovery came after a trip to Belize.

“We kicked over a log and the fish just came crowding out,” Taylor told Reuters in neighboring Guatgemala by telephone. He said he will make his study on the fish known to the public in an American magazine early next year.

In lab tests, Taylor said he found the fish can live up to 66 days out of water without eating.

Some other fish can live out of water for a short period of time. The walking catfish found in Southeast Asia can stay on land for hours at time, while lungfish found in Australia, Africa and South America can live out of water, but only in an inactive state. But no other known fish can be out of water as long as the Mangrove Rivulus and remain active, according to Patricia Wright, a biologist at Canada’s University of Guelph.

Further studies of the fish may tell how animals changed over time.

“These animals live in conditions similar to those that existed millions of years ago, when animals began making the transition（过渡）from water onto land,” Wright said.

49. The Mangrove Rivulus is a type of fish that _______.

由助细胞、反足细胞或极核发育成胚称( )。

The text is written mainly for those_____________.

下列对原文有关内容的分析和概括，不正确的一项是

D

The American newspaper has been around for about three hundred years. In 1721, the printer James Franklin. Benjamin's older brother, started the New England Courant, and that was what we might recognize today as a real newspaper. He filled his paper with stories of adventure, articles on art, on famous people, and on all sorts of political subjects.

Three centuries after the appearance of Franklin's Courant. few believe that newspapers in their present printed form. will remain alive for long Newspaper complies are losing advertisers （广告商）, readers, market value. and. in some cases, their sense of purpose at a speed that would not have been imaginable just several years ago The chief editor （主编） of the times said recently, "At places where they gather, editors ask one another, 'How are you?', as if they have just come out of the hospital or a lost law came. “An article about the newspaper appeared on the website of the Guardian, under the headline “NOT DEAD YET.”

perhaps not, but the rise of the Internet which has made the daily newspaper look slow and out of step with the world, has brought about a real sense of death. Some American newspapers have lost 42% of their market value in the past thee years The New York Times Company has seen its stock （股票） drop by 54% since the end of 2004, with much of the loss coming in the past year A manager at Deutsche Bank suggested that stock-holders sell off their Times stock The Washington Post Comply has prevented the trouble only by changing part of its business to education its testing and test-preparation service now brings in at least half the company's income.

53. What can we learn about the New England Curran?

由额外形成层产生的木质部和韧皮部，分别称为三生木质部和三生韧皮部。( )

花柄长短不等，下部分花柄较长，越向上部，花柄越短，各花排在同一平面上称( )。

根据原文提供的信息，以下推断正确的一项是