Answer:
Feet Above Sea Level
Step-by-step explanation:
A benchmark is a term in Surveying and Geo informatics, that describes a point of reference established at a known elevation which serves as basis in which other elevation or topographical point can be measured.
Therefore, when determining the benchmark, it's height is calculated relative to the vertical datum of the area, typically mean sea level, which is then recorded in FEET ABOVE SEA LEVEL.
Hence, Benchmarks measurements refer to FEET ABOVE SEA LEVEL.
Bah bah black sheep have you any wool yes sir yes sir three bags full
Answer:
:)
Step-by-step explanation:
For simplicity I will substitue
for β.

In the first step I used the identity
And I factored out 
Then it's just simple algebra to cancel till the 3rd step where we used another identity derived from the Pythagorean Theorem.

That's it!
Answer:
44.55
Step-by-step explanation:
I actually didn't get the right answer and I just edited it right now I'm sorry I dont have an explanation!
Multiply first equation with 2. Then add first and second, we get -x=6. X=-6 and y=-29