I usually try and practice changing my mindset. Just try to look at things from another perspective, and if you can't, try thinking the OPPOSITE of what you thought.
Think homework is hard? Say to yourself, "Homework is easy." and trudge on through. After some time, your mindset *will* improve, and your attitudes will change from negative to positive.
Also, try to go out more often. Doing exercise, socializing, all of which will produce serotonin and will improve your outlook on life and attitude.
In short you just multiply 0.480.48 by the amount of miles you drive add that to 24.9024.90 and you get you total for example: if you take the first company if you drive 200 miles per day it will cost you 24.9024.90 with an extra 96.096 wich will add up to 120.99849 in total per day
Since circumference is just pi(we're using 3.14 in this case) * diameter, which is our answer, we need to divide the circumference(which is 7.58) BY 3.14, which is pi. This leaves us with the diameter, which is 2.5. The unit is already feet, so we needn't do anything about that.