7
The snail woke up, crawled from the mushroom to the spring, and fell asleep. The journey took six hours. The snail moved sometimes faster, sometimes slower, and stopped. Several scientists observed the snail. It is known that:

1) At every moment of the journey, the snail was observed by at least one scientist.
2) Each scientist observed the awake snail for one hour (continuously) and says that during this time the snail crawled exactly one meter.

What is the greatest possible distance from the mushroom to the spring?
Example. Let's divide the entire movement time of the snail into 30 intervals of 12 minutes each. Suppose the snail crawls 1 meter in each of the 10 intervals numbered $1,6,7,12,13,18,19,24,25$, and 30, and rests the rest of the time.

Scientists observe it in intervals 1-5 (from 1st to 5th - exactly one hour), 2-6, 7-11, 8-12, 13-17, 14-18, 19-23, $20-24,25-29,26-30$.

See the estimate in problem 73652.

## Answer

$10 \mathrm{M}$.