Help with physics please!

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.

What is the role of lenses in microscopy?

In which type of system is power held solely by the central government and not shared with regional governments? group of answer choices federal unitary confederate oligarchic