Answer:
The equation is not a linear function.
Tell you what I'll do: I'll show you the work, for two of them.
Then, knowing how to do it, you'll find the answers.
Deal ?
#1). n + (-13) = -12
Remove the parentheses
on the left side: n - 13 = -12
Add 13 to each side: n = 1
================================
#3). -15 + n = 3
Add 15 to each side: n = 18
OK. Look those over, understand how they're done, then TAKE IT !
The data set has no association.
If she has 32 miles to the gallon, and 20 dollars, then 5*32 gives you your final answer, which is 160.