The leader's dive watch shows that they descended 33 feet from their starting position. Their current position is now 48 feet below sea level, but there is no record of their starting depth.

Step-by-step explanation:

Given that:

33 feet from their starting position. 48 feet below sea level

So their starting depth mus be the gap between the two milestones mentioned above, we take:

48 - 33 = 15 feet.

So their starting depth is 15 feet below the sea.

Step-by-step explanation:

Given:

Delta D = 33 ft

Dfinal = 48 ft

Delta D = final distance - initial distance

Initial distance = 48 - 33

= 15 ft

= 15 ft below sea level.