Which situation involves a change modeled by a positive number but an end result modeled by a negative number?
Leo enters an elevator on the second floor and goes down four floors.
A plane, flying at an altitude of 300 feet, descends 50 feet.
Irene is scuba diving at –30 feet. She swims 10 feet toward the surface to watch a school of fish.
April owes her brother $5. On Friday, she gets $10 for her allowance.