PLZ help my teacher wants me to do this 34 times 56 reduced by 3 and add 50 i don't know how to answer this PLZ help heres the picture for the question which one is correct

(a) calculate the number of electrons in a small, electrically neutral silver pin that has a mass of 10.0 g. silver has 47 electrons per atom, and its molar mass is 107.87 g/mol. (b) imagine adding electrons to the pin until the negative charge has the very large value 1.00 mc. how many electrons are added for every 109 electrons already present