Which law of motion accounts for the following statement?

"The gravity of the Sun causes the planets to move in a circular path."

When you start with Newton's second law of motion " F = M A ",

AND his law of universal gravitation ... plus a truckload of geometry

and calculus ... you wind up with gravitational orbits, including all of

Kepler's laws of planetary motion. I think those are the only formulas

you need.