Answer:
Jim.
Step-by-step explanation:
Descending results in a greater depth so we add the measurements when they descend and rising results in a lower depth so we minus the measurements when they rise. The surface area has no depth yet, so it is 0 feet depth.
Jim = 8 + 20 - 7 + 12
= 33
Carla = 0 + 15 -7 + 20
= 28
Since 33 feet is deeper than 28 feet, Jim rested at a greater depth.