一次数学竞赛出10道选择题,评分标准为:基础分10分,答对一题得3分,答错一题扣1分,不答不得分。要保证有4人得分相同,至少要有多少人参加比赛?( )
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
免费的网站请分享给朋友吧