第1题
In addition to low fuel bills, many people choose these stoves because their initial cost is very low (the prices range from $ 50 kits to $ 5,000 top-of-the-line models) , and because new technology has made wood fires more efficient, cleaner, and, therefore, safer than ever before.
One new technological feature of this type is the catalytic(催化) combustor which adds about $100 to $ 200 to the cost of the stove, but which causes much more complete combustion(燃烧) of the wood and therefore burns up more of the pollutants left by incomplete combustion and produces more heat.
A second cost-saving innovation is a device which agitates the wood, increasing the amount of oxygen that reaches the center of the wood pile, and leading to more efficient combustion. The real advantage of this device is that it allows the owner to make use of cheap sources of wood such as dirty wood chips ( an industrial by-product) that have almost no commercial value, cost as little as $ 20 a ton, and burn very inefficiently in furnaces without an agitator.
According to the passage, the number of wood-burning stove sold for home use _______.
A.went up fivefold over a six-year period.
B.rose to seven million during the seventies.
C.multiplied thirty-five times between 1973 and the beginning of 1981.
D.increased by 6,000,000 over an eight-year period.
第2题
A.Swapalltellerandassociatemachineswithservers.
B.Swapalltellerandassociatemachineswiththinclients.
C.Swapalltellerandassociatemachineswithlow-profilehigh-endworkstations.
D.Swapalltellerandassociatemachineswithlaptops.
第3题
A.Change to component A form component B . Component A costs more to purchase but has a lower life-cycle cost than B .
B.Change task A to be component B instead of resource C . Resource B is a more experienced worker .
C.Move tasks B and H to occur concurrently, and take the risk of a 30% increase in the need for five more resources later .
D.Delete an acceptance test from the project plan .
第4题
A.extend
B.extent
C.extensive
D.extending
第8题
A.solution
B.sight
C.intellect
D.precedence
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