I assume you meant to write 5^c = 125. The equivalent logarithmic expression for this would be ㏒₅125=c.
X-7=13
move -7 to the right side of the equation, change the sign from negative to positive when you move it
x-7+7=13+7
x=13+7
x=20
B -222
Because he fell/descended 222 meters. And falling or going down produces a negative integer. Also, if you were actually doing the math to try to find where Oliver is currently located, you wouldn't add 222, or 0, or subtract -444. You would subtract 222.
In addition, be aware that the question is asking you an integer to represent a situation, not the answer of where Oliver is.
I think its d but im not sure