If the bicycles belong to ONE FRIEND, it's "friend's bicycles." If the bicycles belong to TWO OR MORE FRIENDS, it's "friends' bicycles."
A disadvantage for glass computer desks would be the inability to support heavier amounts and the ability to break easy.
If the bicycles are otherwise comparable, you'll burn the same amount of calories. If the steel bike is heavier, you'll burn a few more calories on that one.
You would be much heavier on earth- about 12 times heavier.
It is about 400km. So it would take somewhere from 2 days for a fast road cyclists with support, to a week for gentle 60km a day touring cyclists.
?
It's a particular piece of road, dedicated to be used by cyclists.
Total distance divided by total time
Advantage: would help me with me algebra. Disadvantage: would give me bad hayfever.
Because the cycle a lot
Even fatter
If they didn't have engines, they would just be very heavy bicycles.