题目

用如图所示的游标卡尺测量工件，则卡尺读数为_______mm. 答案：29.8解析:游标卡尺有10个分格，其精度为0.1，游标卡尺读数为29 mm，游标第8根刻度线和主尺的刻度线对齐，故游标的读数为8×0.1 mm=0.8 mm，则游标卡尺读数为29 mm+0.8 mm=29.8 mm.I _____ with my parents when he rang me up yesterday afternoon．A. am shoppingB. shoppedC. was shoppingD. shopping