What is the range of normal size of scrotums?

All men have different shapes and sizes for everything.
Did you see him naked on a cold day.
The scrotum can shrink to nothing on a cold day just
like the penis can.
The scrotum shrinks to keep the testis warm which
keeps the sperm alive.
The same applies on hot days the sack with increase
to keep the area cooler and keep the sperm at optimum
temperature.