It depends on the speed at which the runner is travelling.
The answer is actually in the question. 10k is and abbreviation of ten kilometres, therefore a 10k race is 10 kilometres long.
A Betta does not have a "nitrogen cycle"
forty five minutes
It takes about as long as a water cycle
It would take 1 hour and 15 minutes to run 10k at a pace of 8k per hour.
It would take 1 hour 14 minutes 30 seconds.
a long time
I myself cannot cycle to the center of the earth.
28 days
a month
depends on the mountain