A nurse is preparing to administer potassium gluconate 3 mEq/kg/day PO divided in equal doses every 6 hr to a preschooler who weighs 42 lb. Available is potassium gluconate liquid 20 mEq/15ml. How many ml should the nurse administer per dose? (Round to the nearest whole number.)
a) 10 ml
b) 12 ml
c) 14 ml
d) 16 ml