The part farthest from the hand, because it is the last part warmed.
If any other warm substance touch the glass, will the glass be heated in the same manner?
The glass will be heated in the same manner.
What often results from this unequal heating?
The glass is broken.
Why are glass plates or tumblers broken when placed in hot water?
They are broken because the part next to the hot water is expanded more than that farther away.
Why will a cloth dipped in hot water and wrapped around the neck of a bottle loosen its stopper?
Because the heat from the cloth expands the neck of the bottle before it does the stopper, so that the stopper is loosened.
Why do stove-plates often break?