Why do different substances have different properties?

If soap hits the floor, is the soap dirty or the floor

What substance has a mass of 9.5g and volume of 2.1cm^3

Clyde and marilyn are riding a roller coaster. during which section(s) of the track is their potential energy converted to kinetic energy? a. from point b to point c only b. from point b to point d only c. from point a to point b only d. from point a to point b and from point c to point d