1) It tells you in the question c = cost, so cost would be the answer
2) 2.75 is the fixed rate so we would keep it as is. C is the cost which would the total, so c = ?m + 2.75
0.40 per half mile so you put 0.40m because it varies depending on the amount of miles
That makes the equation c = 0.40m + 2.75
3) Now to find how much it costs for 45 miles, you plug 45 for m
c = 0.4 * 45 + 2.75
c = 20.75
Not sure why it isn't an option