2) Across the bridge
There are two islands, and a bridge between the islands. On one
island stands four people. They all take a different time to cross
the bridge - 10 min, 5 min, 2 min and 1 min.
However, there is only ONE torch amongst these people, and they
HAVE to use the torch to get across the dark bridge. The bridge,
being rickety and all, can only hold a maximum of 2 people at one
time, or it will break.
How long will it take for everyone to get to the other island, and
how? (no tossing torch across the waters!)
