Our science club built a catapult out of craft sticks, glue, and a rubber band. We wanted to determine what size rubber band was best for launching a gumball across the classroom. If the rubber band was too small, the gumball wouldn’t travel very far. If it was too big, it would be too loose to work well. We found that a rubber band with a circumference of 11 cm shoots the gumball the farthest Independent variable:
Control variables:
Dependent variable:

explanation:

newton's third law, for every action there is an equal and opposite reaction.

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note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.