What number is 40% of 15? Round to the nearest hundredth

This is so hard and it’s for a test

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.

Which graph of a hyperbola represents the equation 16x^2-y^2=16