Answer:
The answer is -45.3 feet depth. while minus sign shows the descend under the water with water surface as starting point.
Explanation:
Initial depth of diver under the water

Diver descends 5 feet per minute for 3.5 minutes


Note: minus sign shows that the diver is under the water.
Diver ascends

Now adding all the terms a below as a numerical expression.
Current Depth of Diver after he descends 5 feet for 3.5 minutes and ascend 122.2 feet after


By taking the initial depth of diver from which we add or subtract the changes made when he ascends or descends in the water to get the current depth.