题目

弹簧秤是由外壳、弹簧和挂钩三部分构成,每只弹簧秤的外壳重0.3N,弹簧质量可以忽略,挂钩重0.1N,弹簧处于自由长度时,示数为0,两只同样的弹簧秤,甲“正挂”,乙“倒挂”,在乙的下方挂上重0.5N的砝码,用手提甲的上方,并保持静止,则甲、乙弹簧测力计的读数分别为( ) A . 0.8N,0.5N B . 0.8N,0.8N C . 1.0N,1.0N D . 1.0N,0.8NHarry _________ by the investigating committee yesterday. A. was called up   B. called up      C. calling up     D. be called up  
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