Answer:
This should be shown as:
-250 + 80 - 18 = - 118
Step-by-step explanation:
Going down 250 feet will mean going down feet 250 so it will be -250. Rising 80 feet will mean going up 80 feet so it will be adding 80. Finally, descending 18 feet will mean going down 18 feet, so it will be -18. If you put them all together as one equation, you will get -250 + 80 - 18 which is -118.
Hope this helps!