Question

all metals melt in a high tempreater

Answer 1

some metals if O2 is provided will burn.....

Answer 2

false. mercury

Answer 3

mercury is a metal and it is in liquid state at room temp.
also alkali metals heated at low temp. melt easily

Answer 4

hmm if the question means "all metals must melt at high temp" then it's false, as JFraser said, because mercury, gallium, etc melt as about room temp.

If the question means "all metals are molten at high (including all temperatures below)" meaning that all metals do melt, then it's true.