Answer:
The general rule is 
Step-by-step explanation:
Arithmetic sequence:
In an arithmetic sequence, the difference between consecutive terms is always the same, and this difference is called common difference.
The general rule of an arithmetic sequence is given by:

In which
is the first term and d is the common difference.
We can also find the nth term as a function of a term m, using:

a3 = -12 and a8 = -37
First we find the common difference. So






So

Finding the first term:

Since 



So the general rule is:


It’s 56 bc a straight line = 180 so 180-124=56
All angles in triangle inside add up to 180
so
the angles are y, 79,37
therefor
y+79+37=180
solvde for y
y+79+37=180
add
y+116=180
subtract 116 from ot hsides
y=64
angle y=64 degrees
To answer this i need a little more info but it's probably going to be 30 miles.