The cetane number of a diesel fuel oil indicates its（）

A . Size of typical transactions  B . Concurrent transactions  C . Size of rows in table most frequently changed  D . Number of anticipated disk sort

A . ignition quality of the fuel B . calorific value of the fuel C . flash point of the fuel D . rate of fuel consumptio

A . less fuel will enter the cylinder B . higher the cylinder combustion temperature C . more complete the fuel combustion D . more rapid the rise in combustion pressure

A . The cetane number is obtained by comparing the fuel with cetane a colorless liquid hydrocarbon B . The higher the cetane number, the shorter the ignition lag C . The highest cetane number of fuel is 100 D . All of the above

A . backwards B . forwards C . upward D . downward

A . the worse B . the better C . the smaller D . the greater

A . the number of packets that are discarded because they exceed the maximum packet size of the medium B . errors created when the CRC generated by the originating LAN station or far-end device does not match the checksum calculated from the data received. C . the number of packets that are discarded because they are smaller than the minimum packet size of the medium D . the number of received packets that were ignored by the interface because the interface hardware ran low on internal buffers E . the number of times that the interface requested another interface within the router to slow dow

A . was B . were C . be D . have

A . Have B . Has C . Has there been D . Are there

A . heavy rain B . heavy snow C . thick fog D . clearing skie

A . is stated on the vessel's Certificate of Inspection B . is the number authorized in the Navigation Rules C . depends on the number of lifejackets you carry D . is the number authorized by your license

A . The cetane number has no affect on injection lag B . The cetane number is an indication of the fuel’s viscosity C . Ignition lag is reduced with fuels having a high cetane number D . The cetane number is of little significance in the combustio

A . The cetane number affects the amount of injection lag B . The cetane number is an indication of the fuels viscosity C . Ignition lag is reduced with fuels having a high cetane number D . The cetane number is of little significance in the combustion proce

A．Y B．N C．NG

A．Right B．Wrong C．Not mentioned

A．A.flood B．B.drought C．C.premiere D．D.misery

A.antiknock characteristics B.ignition qualities C.rates of vaporization D.viscosity

A．Right B．Wrong C．Not mentioned

是 否

A．n B．l C．m l D．m s

But, there's another side. SARS is a reminder of how fragile (脆弱的)life can be. Suddenly, it's not just the old people who are thinking about death. Everyone now realizes there might not always be a tomorrow. Li Ping, a Senior 3 student in Taiyuan, Shanxi Province, came into contact(接触)with a suspected(疑似)SARS patient in mid-April. He was told to stay at home for at least two weeks. "Watching TV about more and more SARS patients dying, ! never knew that death could be so close. Life is Valuable and I am going to treasure every single day." he said. SARS teaches people to be grateful, not only for their own lives, but also for others. Doctors and nurses, for example, have to spend all their time with infected(被感染的)patients. As a result, more than 20 percent of SARS cases in China are medical workers. Liu Yu, a Senior 2 student of Beijing No. 5 Middle School, wants to be a doctor when he grows up. "Although they certainly know of the dangers, doctors and nurses remain bravely dedicated(致力于)to saving people's lives. I was deeply moved by what they have done. I think they are real heroes." he said. SARS also teaches sympathy(同情). The past few weeks have been terrible for Chinese people. But there are far worse things than SARS in this world, such as war, earthquakes and murders. Think of the Iraqis, who have been living terrible lives for 20 years. Think of how the Americans felt on 9. 11. And finally, SARS offers the chance to grow. All different types of people and government officials are joining together to cope with this difficult time. When this passes, China and its people, will have learned great lessons. The story of Li Ping is given in this passage mainly to ______. A．tell us the hardship of life B．tell us the fragility of life C．tell the cruelty of SARS D．tell us the joy of life