1. the last one
2.the first one hope this helps.

This result is actually true for any exterior angle. The exterior angle of a triangle is equal to the sum of the two remote angles, and above is a short proof of it.
Here the answer is: 0.76 and 1.84
I hope I don't have to explain it again.
It could be either y = 12.75x or y = 13x. Check if you made a typing error because these rates are both better than B