It was used to tell the time and knowing the time even the aproximate time is quuite useful
it is useful because you do not need to wait for a long time just a short time
Depends on what you call 'useful'. If it is useful to learn how to kill hundreds of people in the shortest amount of time, and to learn how to castrate hundreds of men in the shortest time, then, yeah, they were useful.
mutations are useful but not all the time itis 99 percent are bad
they will show the variation between distance & time
Studying time management techniques is useful for increasing productivity.
time management
When it is the right time
A: Most useful or actually the only time that it is useful is when it has reached its predictable reverse breakdown voltage.
to locate place and for time calculation
The time for cooking is lower.
Yes, they were very useful