If walking out side in the cold temps how would a thermos keep a drink hot compared to an open a new closed system?

Question

conley39 · Answer

There's a vacuum between the inner and outer walls of the thermos that acts as insulaion preventing the transfer of heat.

CB · Answer

Step away from the bong dude and try again.

THERMOS - a container that keeps a drink or other fluid hot or cold by means of a double wall enclosing a vacuum.

kswck2 · Answer

Try that one again. Say What?