题目

某种零件，标明要求是φ25±0.2 mm（φ表示直径，单位：毫米），经检查，一个零件的直径是24.9mm，该零件____________（填“合格”或“不合格”）. 答案：【答案】合格【解析】根据φ可知，零件的最大直径为：，最小直径为，直径在到之间的零件为合格.解：∵φ，∴零件直径最大值为：，零件直径最小值为：，合格范围：φ∵在该范围内，∴该零件合格，故答案为：合格.Only when your identity has been checked__________. A. you are allowed to come in B. You will be allowed to come in C. will you allow to come in D. will you be allowed to come in