Plzzz answer this question correctly

The heliocentric and the geocentric models of the solar system included these central principles

Aheavy boy and a lightweight girl are balanced on a massless seesaw. the boy moves backward, increasing his distance from the pivot point. what happens to the seesaw? it is impossible to predict without knowing additional information. the side the boy is sitting on will tilt downward. the side the girl is sitting on will tilt downward. nothing; the seesaw will remain balanced.

What are the differences and relationships between speed, velocity, and acceleration