A.15 minutes.B.20 minutes.C.10 minutesD.25 minutes.
A.15 minutes.
B.20 minutes.
C.10 minutes
D.25 minutes.
A.15 minutes.
B.20 minutes.
C.10 minutes
D.25 minutes.
A、30
B、60
C、90
D、120
B.The famous stars on "Sesame Street".
C.The children can learn and want to learn more.
D.The children can understand.
A.Water shortages in cities.
B.Earlier thawing of lakes and rivers.
C.Increased levels of greenhouse gases.
D.The rapid extinction of the polar bear.
A.Y
B.N
C.NG
B.To do it in an organized way.
C.Not to get too close to a storm.
D.To spend more time on it in summer.
Imaginations were fired. Men dreamed of going to work in their own personal helicopters. People anticipate that vertical flight transports would carry millions of passengers as the airliners of today do. Such fantastic expectations were not fulfilled. The helicopter has now become an extremely useful machine. It excels in military missions, carrying troops, guns and strategic instruments where other aircraft cannot go. Corporations use them as airborne offices, many metropolitan areas use them in police work, construction and logging companies employ them in various advantageous ways, engineers use them for site selection and surveying, and oil companies use them as the best way to make offshore and remote work stations accessible to crews and supplies. Any urgent mission to a hard-to-get-to place is a likely task for a helicopter. Among their other multitude of uses: deliver people across town, fly to and from airports, assist in rescue work, and aid in the search for missing or wanted persons.
(30)
A.Helicopters have only been worked on by man since 1940.
B.Chinese children were the first to achieve flight in helicopters.
C.Helicopters were considered more dangerous than the early airplanes.
D.Some people thought they would become widely used by average individuals.
A.people spent more money than they earned
B.people saved more money than before
C.people spent their money wisely
D.people invested and consumed at an accelerated pace
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