— Can you tell me it is from here to the history museum?— It’s about half an hour’s walk.

问题补充：

— Can you tell me it is from here to the history museum?

— It’s about half an hour’s walk.

A. how much

B. how often

C. how long

D. how far

答案：

A. how much

B. how often

C. how long

(答案→)D. how far

解析：D 根据答语“步行大约半小时”可知，问的是距离，对距离提问用how far。how long是对时间提问；how often问频率；how much问价钱。