小明和小亮在操场上跑步，小明跑一圈用4分钟，小亮跑一圈用3分钟。他俩同时出发后，经过（ ）分钟又同时回到起点。
12
票据的（ ）日期必须使朦胧和中文大写
A．结算
B．交易
C．往来
D．出票
— Could you tell me _____ it is from here to the science museum?
— It's about half an hour's walk. [ ]
A. how far
B. how long
C. how soon
