The arithmetic sequence below shows the costs, in dollars, of riding 1,2,3, and 4 miles (and so on) in a certain taxicab. 5.30, 7.80, 10.30, 1280, ...
Which function represents the nth term of this sequence, for n = 1, 2, 3, 4, ... ?
f(n) = 2.80+ 2.50n
f(n) = -2.50+ 7.80n
f(n) = 5.30+ 7.80n
f(n) = 5.30 + 2 50n