Hyponatremia Calculator

Insane cool, but.. i do not know how to calculate it i tried looking for a naᵨ calculator.! I tried asking my parents if they knew about it, and sadly, No, they did not know my grandma wasn’t helping cause I wanted to measure the grams, and instead, she wrote on a paper, wrote: what i had for breakfast and then, i wanted her to leave me alone for a couple minutes. (: