Nitrogen, oxygen and argon are obtained from liquid air by fractional distillation. State the physical property that makes this possible​

Asolution contains 225 g of sodium chloride, nacl, dissolved in enough water to make a 0.25 l of solution. what is the molarity of the solution? a. 3.88 m, b. 1.03 m, c. 1.5 m, d. 15.5 m

Earth's axis of rotation is tilted at an angle of 23.5 degrees. what is one change you would see on earth if its axis was not tilted?

Answer asap : ( a. how does mucus prevent the entry of pathogens? b. describe two ways white blood cells protect us from pathogens.