C++ :: Error - Else With No Matching If

Here is my first program, I had to use a lot of if/ else statements. For some reason the last "else" (bolded) is giving me an error and not letting me run the program.

#include <iostream>
using namespace std;

const float MILES_PER_KM = 1.0 / 1.61;
const float KM_PER_MILE = 1.61;
const float FREEZING_F = 32.0;
const float FAHR_PER_CELSIUS = 9.0 / 5.0;
const float CELSIUS_PER_FAHR = 5.0 / 9.0;
const float MAX_F_TEMP = 100.0;
const float MIN_F_TEMP = 0.0;

[Code] ....

And yes, the if else's are indented properly, because there are no errors for the first 3 unit types, only for the last one ( 'F' ), and i have them all exactly in the same format.