题目

甲、乙两同学进行拔河比赛,若甲对绳的拉力为F甲,乙对绳的拉力为F乙, F甲与F乙均沿绳子方向,比赛中绳子做匀速直线运动,最后甲取胜绳重不计,则绳子受到的拉力F甲、F乙以及这两个力的合力F的关系是                 AF甲>F乙,F=F甲+F乙                    BF甲<F乙,F=F甲-F乙 CF甲=F乙,F=0                          DF甲=F乙,F=F甲+F乙 . She pretended ______ me when I passed by . A.not to see . B.not seeing C.to not see D.having not seen.
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