Answer :
Answer:
They are 152 feet underground.
Step-by-step explanation:
Based off of 0 being sea level, or ground level:
They started 84 feet underground. So that is -84 [feet].
They took an elevator 123 feet down. So that is -123 [feet].
... And then they rode mine carts 55 feet back up. So that is +55 [feet].
Now all we have to do is add them up!
(-84) + (-123) + 55 = ?
|_______|
-207 + 55 = ?
|_______|
- 152 = ?
So they are 152 feet underground!
I hope this helps!
PLEASE MARK BRAINLIEST!