Constant is occurring continuously over a period of time so C is the correct answer because C is constant for a period of time
3000 + 70 + 2
It's basically everything that is added to get that number. You do not need a 100's place because a 0 is holding that spot.
<em>x = 1</em>
<em><u>Here is why:</u></em>

Add x to both sides.

Add 5 to both sides.

Divide.
x = 1