Issued as a cumulative or non-cumulative L/C, the former allows for unused credit amounts to rollover into subsequent periods while the latter maintains a fixed amount of credit available each period.
average atomic mass of magnesium is 24.3 g/mole so 24.3 X 1.56 X1021 / 6.02 X1023 = .063 grams.
The adult human daily requirement of magnesium is about 0.3 g day-1. 1  Name: magnesium. 2  Symbol: Mg. 3  Atomic number: 12. 4  Relative atomic mass (Ar): 24.3050 (6) 5  Standard state: solid at 298 K. 6  Colour: silvery white. 7  Classification: Metallic.