One point charge has a magnitude 5.4x10-7 C. A second charge 0.25 meters away has a magnitude of 1.1x10-17 C. What is the electric force magnitude of one charge on the other

The experiment done in lab is repeated, using a ball that has unknown mass m. you plot your data in the form of f 2 versus m/l, with f in rev/s, m in kg, and l in m. your data falls close to a straight line that has slope 3.19 m/(kg · s2). use g = 9.80 m/s2 and calculate the mass m of the ball.