The grand canyon is approximately 2^9 kilometers long. mariner valley is a canyon on mars that is approximately 2^12 kilometers long. about how many times longer is mariner valley than the grand canyon? a. 2 b. 2^3 c. 2^21 d. 2^108

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.