Answer: -300 meters
Step-by-step explanation: If he started from 0 (sea level) and went 300 meters under, meaning 0-300=-300 meters.
A) $15 ÷ 40% =
15×.4= 6
15+6= 21
B) $38 × .25=9.5
38-9.5=28.50
28.50×.06=1.71
28.50+1.17=30.21
I think this is how you do it. would wait for other answers as well to double check.
If you mean "how to write the sum", the answer is

The result of this sum is
, because you start from 2 on the number line and take 3 steps to the left (negative integers mean going left, positive integers mean going right)
e + 1 13/16 = 2 5/16
subtract 1 13/16 from each side
e = 2 5/16 - 1 13/16
borrow from the 2
e = 1 16/16 + 5 /16 - 1 13/16
e = 1 21/16-1 13/16
e = 1 8 /16
e = 1 1/2
X ⇒ ln (2)
e^3 x - 8/e^2 x - 4