6.2km in 39 mins. hmm so if 10km it'll be abt 63 min. still a bit slow. if i wanna do 10km in 1 hr it means
2.4km in less than 14.4 mins
3km in less than 18 mins
6km in less than 36 mins

Maybe I should improve on my 2.4km timing first...don't know if 13 min flat is possible or not.

heard a funny statement from a returned colleague "傻事做一次就好".