在磨铣施工过程中，每磨铣完1根钻杆要充分洗井，时间不少于（）
A、5min
B、10min
C、20min
D、60min
参考答案：C
Alice is sitting ________ two students. The one on her left is Mary and the one on her right is James. [ ]
A. behind
B. between
C. in front of
D. across from
