Selling Price = $145
Charge on first $25 is 5.25%
5.25% of $25 =
Charge on rest is 3.25%
rest amount = $145 - $25 = $120
3.25% of $120 =
Sin B = opp/hyp
sin B = 3/5
It leaves Chicago at 11:49 am and takes 2 hrs 26 min.
So in central time, that gets you to Denver at 2:15 PM.
Since mountain time is one hour behind central time, your answer would be 1:15 PM.