Put the elements in order from the highest electronegativity at the top of your list, to the lowest at the bottom. germanium (ge) gallium (ga) arsenic (as) bromine (br) rubidium (rb) selenium (se)

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.