[判断题]改、扩建工程中，在室内高压设备上或某一间隔内作业时，在作业地点两旁及对面的间隔上均应设围栏并挂“在此工作!”的安全标志牌。( )
A.正确
B.错误

Most people who travel long distances complain of jetlag (喷气飞行时差反应). Jetlag makes business travelers less productive and more prone (21) making mistakes. It is actually caused by (22) of your "body clock"—a small cluster of brain cells that controls the timing of biological (23) . The body clock is designed for a (24) rhythm of daylight and darkness, so that it is thrown out of balance when it (25) daylight and darkness at the "wrong" times in a new time zone. The (26) of jetlag often persist for days (27) the internal body clock slowly adjusts to the new time zone. Now a new anti-jetlag system is (28) that is based on proven (29) pioneering scientific re- search. Dr. Martin Moore-Ere has (30) a practical strategy to adjust the body clock much sooner to the new time zone (31) controlled exposure to bright light. The time zone shift is easy to accomplish and eliminates (32) A. on
B. with
C. for
D. in