题目内容
（请给出正确答案）
A.Message authentication code
B.Ciphertext authentication code
C.Cyclic redundancy check
D.Electronic digital signature
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Pressure Cooker (压力锅) Safety
When you are cooking with a pressure cooker, you should learn a few common sense(常识)rules:
1 . Never leave the cooker unwatched when it is in use.
2. Add sufficient liquid but never past the recommended fill point. Overfilling the colder may block the vent pipe (排气孔) and cause the cooker to explode.
3. Set the cooking time. Too much time may overcook the food or too much pressure may build up in the cooker. Too little time will lead to undercooked food.
4. If you are new to pressure cooking, follow the cooking instructions carefully. Heat and time can either result in a great meal or a ruined one.
5. Never try to force a pressure cooker cover open, Allow the cooker to cool or run it under cool water before trying to open the cover.
6. Clean the cooker thoroughly after each use . Mild detergent(洗涤剂)and hot water work the best.
Do not use stove ash or sand for they may damage the cooker. The gasket(密封圈)is best cleaned in warm soapy water and then dried. Store the gasket in the bottom of the pot.
According to the first rule, the user should______ .
A．keep the cooker under close watch
B．always keep the colder half full
C．never leave the colder empty
D．never turn off the stove
Stars smaller than the Sun and up to eight times as massive die by swelling up into red giants before shedding most of their mass to shrink into very compact, dying embers(灰烬) called white dwarfs. Two kinds of red giants exist-those with lots of carbon, and others richer in oxygen than in carbon. Carbon-rich stars release carbon particles during their death throes. Scientists proposed these pitch-black grains absorb rays from the dying star and get shot into space by starlight, a theory that fit both the observations and computer models.
Increasingly, however, researchers could not explain how oxygen-rich stars like our own Sun could propel their clouds away during the final stages of mass loss. Oxygen-rich stars create large quantities of water vapor and silicates, such as quartz(石英砂) or sand. These are transparent, meaning starlight should go right through them.
Possible solutions have been contemplated by scientists. They first pondered whether the silicates might have iron in them, which would render them opaque instead of transparent. But calculations showed the dust grains would have evaporated if they had iron in them. They next wondered if enough molecules surrounded the core of a dying oxygen-rich star to block out its light and thus create a wind that blew the star's outermost layer into space. But their models suggested these molecules could not block off enough light and create strong enough Rinds.
The scientists then suggested that pulsations occurred when stars die could perhaps force a star's matter out, but this idea did not match with astronomers' observations. But inspiration then dawned upon them. Perhaps some of the carbon in the oxygen-rich stars could help force the outer layers of the stars into space. They believe shock waves from the pulsations of dying stars could make carbon in oxygen-rich stars form. pitch-black dust.
"The theory fits with all our subsequent model calculations, and it matches observations from dying oxygen-rich red giants". Moreover", this mechanism strongly favors the presence of magnesium silicates over iron silicates in the interstellar medium", in agreement with recent findings from NASA's comet-sampling Stardust space probe. If proven correct, the beauty of the new scenario is that it suggests a common driving mechanism for many dying stars shedding their mass via dusty winds", with possible long-reaching consequences for the origin of chemical elements relevant for life".
By introducing the theory of red giant, the author intends to ______
A．explain-the possible way of death of our Sun.
B．show the two types of red giants.
C．discuss on the way of red giants to become white dwarfs.
D．explore the origin of life.
But prominent federalists are also unimpressed. Guy Verhofstadt, a former Belgian prime minister, speaks for many in Brussels when he denounces Mr. Barroso for a lack of ambition for Europe. Mr. Verhofstadt invokes the memory of Jacques Delors, the pugnacious Frenchman who ran the commission from 1985 to 1995．Mr. Delors proposed many ambitious plans, he says, and got 30% of them: that 30% then became the European internal market. Mr. Verhofstadt thinks that last autumn Mr. Barroso should have proposed such things as a single EU financial regulator, a single European bad bank, or a multi-trillion issue of "Eurobonds". That would have triggered a " big fight" with national governments, he concedes. But "maybe the outcome would have been 10%, 20% or 30% of his plan. "
The French president, Nicolas Sarkozy, has endorsed a second tenn for Mr. Barroso, a former centre-right prime minister of Portugal. Yet he seems keen to make him sweat. French officials have briefed that the decision on Mr. Barroso's future taken at the June 18th-19th summit should be only political, leaving a legally binding nomination for later.
Yet the attacks on Mr. Barroso are unlikely to block him. No opinion poll shows the PES overtaking the centre-right European People's Party in the European Parliament. The centre- right leaders who hold power in most of Europe have endorsed Mr. Barroso, as have the (nominally) centre-left leaders of Britain, Spain and Portugal. This helps to explain why the PES, for all its bluster, has not fielded a candidate against Mr. Barroso.
It is equally wrong to pretend that Europe was ready for a federalist big bang last autumn. Officials say Mr. Barroso spent the first weeks of the economic crisis bridging differences between Britain and France on such issues as accounting standards and the regulation of rating agencies. Later, he kept the peace between Mr. Sarkozy and the German chancellor, Angela Merkel, after the French president pushed for summits of EU leaders from euro-area countries (Ms Merkel thought that sounded like a two-speed Europe). In any case France has no veto over Mr. Barroso's reappointment: the decision is now taken by majority vote. Some diplomats suggest that France's stalling tactics are meant to extract such concessions as a plum portfolio for its commissioner.
Those calling for "European" action often talk as if they are describing an elegant mechanism, needed to make the union work properly. They argue that only a single financial regulator can police Europe's single market, or complain that 27 national bail-out plans lack "coherence". In fact, these apparently structural calls for "more Europe" are pitches for specific ideological programmes. Thus, in a joint statement on May 30th Mr. Sarkozy and Ms Merkel announced that "Liberalism without rules has failed. " They called for a European economic model in which capital serves "entrepreneurs and workers" rather than "speculators", and hedge funds and bankers' pay are tightly regulated. They added that competition policies should be used to favour the "emergence of world-class European companies", and gave warning against a "bureaucratic Europe" that blindly applies "pernickety rules". If all this sounds like Europe as a giant Rhineland economy, that is no accident.
Mr. Verhofstadt, a continental liberal, means
A．Barroso adopts policies that are in favour of market economy rather than social welfare.
B．Barroso does not care about European people.
C．Barroso suggests EU establish more markets for the convenience of European people.
D．Barroso is the owner of many markets in Europe.
Section A (30 points, 2 points each)
Directions: This part is to test your reading ability.There are 3 tasks for you to fulfill. You should read the materials carefully and do the tasks as you are instructed.
Last night after dinner I told my family the bad news. 1 had this class assignment to monitor our use of energy at home for a week. Our family got an F.
Tuesday night my brother watched the same two hour movie on his TV set that we were watching in the living room. Thursday Mom ran an entire dishwashing cycle for 3cupa, 2plates, a knife and 3 little spoons. That's lot of electricity and hot water down the drain.
Dad drives 28 miles back and forth to work alone. Two men he works with live right nearly, and they could carpool(合伙使用汽车) and save about a thousand gallons of gas a year. And me, I'm guilty too. I went out and left the radio blaring in my room all Saturday morning.
So last night at the dinner table we all agreed to do everything we could to conserve energy. Faster showers. Lower thermostats(温度调节器) . Fuller care (51) It's a fact that this country's using up energy faster than we produce it. I read that we may run out of oil-forever-in thirty years. So terrible. (52) Unless every person in every house on every block does his part, the future looks pretty dim.
I'm getting more and more concerned about the future. Because that's where I'm going to be.
The people in this family______.
A．wasted energy unconsciously
B．had the radio on when they went out
C．watched TV programs separately
D．liked to use hot water while washing dishes
A.从namenode上获取数据
B.从datanode上获取block位置
C.从namenode上获取block位置
D.从namenode上获取数据和block位置
