There are several different models that represent compounds. One type of model is shown.

A large black sphere connected to 4 small blue spheres by 4 grey sticks.
What type of model is shown?

a structural formula
a chemical formula
a space-filling model
a ball-and-stick model

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