A roller coaster starts from a deck at an elevation of 20 feet above the ground. On the first hill it climbs 78 feet and then drops 85 feet. On the second hill the coaster climbs 103 feet and then drops 110 feet. How far below or above the deck is the coaster after the completion of the two hills? A)14 feet below B)14 feet above C)6 feet below D)6 feet above