Which of the following elements is considered as a metalloid?

An evacuated glass vessel weights 40.0g when empty, 135.0g when filled with a liquid of density 0.95 g mL^-1 and 40.5 g when filled with an ideal gas at 0.82 atm at 250 K. The molar mass of the gas in g mo^-1 is:

(Given: R = 0.082 L atm K^-1 mol^-1)

Element “E” belongs to the period 4 and group 16of the periodic table. The valence shell electron configuration of the element, which is just above “E” in the group is