What volume is occupied by 0.25 moles of nitrogen gas at 360 K and 1.50 atm

Iknow #2 is d. i just need to know why

Sally is making a model of a magnesium atom with an atomic mass number of 24 for her chemistry class. she has foam balls for the protons, neutrons, and electrons. she has added 6 neutrons to her model so far. how many more neutrons does she need to add to complete her neutral atom of magnesium?

Name the element in group 17, period 2. (periodic table)