How many moles of NaCl would you have in 100 mL of this solution?

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

Afusion reaction takes place between carbon and another element. neutrons are released, and a different element is formed. the different element is a) lighter than helium. b)heavier than helium. c)the same weight as helium. d)dependent on the element that reacted with carbon.

Find the midpoint of a segment with endpoints of 4-3i and -2+7i