Get 1000 flies. Take 500 and put them in a jar in the fridge. Put the other 500 in a jar and keep it in the warm house. Check both jars after 12 hours and see how well the flies in each jar are doing.

They avoid cool areas

Yes.

yea

Flies do not hate, but when it is too cold they cannot be active. They will just stay asleep, or die if it gets much too cold.

yes, i think so