HELP PLEASE! Find the 15th term of the sequence defined by the explicit rule

f(n)=4n-3

The inside wheels of a car traveling on a circular path are rotating half as fast as the outside wheels. the front two wheels are six feet apart. what is the number of feet in the path traced by the inside front wheel in one trip around the circle? express your answer in the form "k \pi", where k is an integer.

You paid 28.00 for 8 gallons of gasoline. how much would you pay for 15 gallons of gasoline?

Bernice paid $162 in interest on a loan of $1800 borrowed at 6%. how long did it take her to pay the loan off?