题目

PART FOUR WRITING SECTION A Directions: Read the following passage. Fill in the numbered blanks by using the information from the passage.      Write NO MORE THAN THREE WORDS for each answer. The girls in this sixth grade class in East Palo Alto, California, all have the same access to computers as boys. But researchers say, by the time they get to high school, they are victims of what the researchers call a major new gender (性别) gap in technology. Janice Weinman of the American Association of University Women (AAUW) says, Girls tend to be less comfortable than boys with the computer.如图所示，振源S上下做简谐运动，其振动频率为50Hz，所产生的简谐横波向右传播，波速为40m/s．P、Q是波传播途中的两个质元，已知SP=4.8m，SQ=5.4m．则当振源S恰通过平衡位置且向上运动时，关于此时P、Q两质元的位置，下列说法正确的是（　　）A．P、Q都在波峰B．P在波峰，Q在波谷C．P在波谷，Q恰通过平衡位置向下运动D．P恰通过平衡位置且向上运动，Q在波峰