If glоmerulаr filtrаtiоn intо the Bowmаn’s capsule is 700 mEq/day and 450 mEq/day is reabsorbed in the proximal tubule, 200 mEq/day is reabsorbed in the thick ascending loop of Henle and 30 mEq/day is secreted into the collecting tubule, what is the amount that is excreted?