Answer:
54
Step-by-step explanation:
Answer:

Step-by-step explanation:
Given


See attachment
Required
Find 
First, calculate 
--- angle on a straight line
So, we have:

Collect like terms


Next, calculate PQR

So, we have:

Collect like terms


So, PRO is calculated as:
--- angles in a triangle
So, we have:


Collect like terms


Answer:
-85.9 feet below sea level.
Step-by-step explanation: