At a restaurant you only have $20 to spend on dinner. in addition to the cost of the meal you must pay a 5% sales tax and leave a 15% tip. what is the most expensive item you can order?

Johnny rode his bike to a friends house 4 blocks down the street in his neighborhood. he immediately rode back home once he realized his friend was unable to play. what was his displacement for the total bike ride trip? what could you use as a reference point ? show the steps to solve this problem.