What mass of PCl5 will be produced from the given masses of both reactants? 28 and 60?

The answer for #3 is c but i don't know why

Click the button that shows the correct relationship of the electron affinities of the elements sodium and phosphorus. sodium’s electron affinity value is more negative than the electron affinity value of phosphorus. phosphorus’ electron affinity value is more negative than the electron affinity value of sodium. this information cannot be determined using the periodic table. answer is b on e2020.

Which liquid (h2o, h2o + soap, or h2o + salt) has the strongest cohesion and adhesion? (need now plz)