2.41. 第41题接地体的材料的是钢材,人工接地体水平敷设的可以采用圆钢、扁钢,垂直敷设的可采用角钢、钢管、圆钢等()
是
是
A.连接前不需清除连接部位的氧化物
B.连接前应清除连接部位的氧化物
C.扁钢搭接长度应为其宽度的4倍,并应四面施焊
D.圆钢搭接长度应为其宽度的4倍,并应四面施焊
根据以下材料回答第 41~45 题:
Passage Three If you want to stay young , sit down and have a good think. This is the research result of Professor Faulkner , who says that most of our brains are not getting enough exercise and as a result, we are ageing unnecessarily soon.
Professor Faulkner wanted to find out why healthy farmers in northern Japan appeared to be losing their ability to think and to reason at a relatively age , and how the process of ageing could be slowed down.
He set about measuring brain volumes of a thousand people of different ages and occupations.
Computer technology enabled him to obtain precise measurements of the volume of the front and side sections of the brain , which relate to intelligence and emotion, and determine the human character.
Contraction of front and side parts—as cells die off –was observed in some subjects in their thirties, but it was still not evident in some sixty-and seventy –year-olds.
Faulkner concluded from his tests that there is a simple way to slow the contraction-using the head.
The findings show that contraction of the brain begins sooner in people in the country than in the towns. Those least at risk, says Faulkner, are lawyers , followed by university professors and doctors. White-collar workers doing routine work are, however, as likely to have shrinking brains as the farm worker, bus driver and shop assistant.
Faulkner’s findings show that thinking can prevent the brain from shrinking. Blood must circulate properly in the head to supply the fresh oxygen the brain cells need. “The best way to maintain good blood circulation is through using the brain , ” he says,” Think hard and engage in conversation. Don’t rely on pocket calculators.”
第 41 题 Professor Faulkner wanted to find out_________ .
A.how people’s brains shrink
B.the way of making people live longer
C.the size of certain people’s brains
D.why certain people aged sooner than others