You are out of Robitussin AC, a cough syrup that contains 10 mg of codeine per 5 ml. You can make Robitussin-AC by adding codeine injection to Robitussin. If the codeine injection strength is 200 mg/ml, how many ml of the injection will you add to a 100 ml bottle of Robitussin to produce the same amount of codeine as in Robitussin-AC?