专四专八考试

【单选题】The exploitation of the power in the Sun’s rays is a form of alternative energy now showing new commercial promise.
In the US, manufacturers have made important (26) in the development of the technology to bring down the cost of solar conversion systems (27) improving their reliability.
The direct conversion of solar (28) electrical energy, using photovoltaic cells (29) distinct advantages as an alternative energy option.
(30) other forms of renewable energy, photovoltaic is based on modular solid state devices which can be mass (31) at a relatively low cost.
Here wafers of silicon—not dissimilar (32) ones which are turned into silicon chips— (33) an electric current when light falls upon them.
When built into panels or modules where each cell interconnects, the amount of electricity generated can be large enough to (34) a home or even a community.
Over the past 10 years, (35) extensive research and substantial Government and private industry funding, the price of photovoltaic modules has dropped (36) .
(37) in 1973-74 the price per peak watt was between US $100 and $150, commercial prices for small array system now vary between $6.50 and $7 per watt.
This rapid price reduction has been accompanied by a 400 per cent jump in the (38) efficiency of photovoltaic modules.
(39) solar cells are poor converters of sunlight to electricity.Early cells could only manage to mm about five per cent of the incident rays into electricity, but recent development have increased (40) to more than 10 percent.
A．perspective
B．regular
C．average
D．spontaneous

网考网参考答案：C
网考网解析：
average意为“平均”。此处意为“在光电模块的平均效率上”。A) perspective“透视的”；B) regular“规则的”；D) spontaneous“自发的”。 document.getElementById("warp").style.display="none"; document.getElementById("content").style.display="block"; 查看试题解析出处>>