The four giant gas planets that are made primarily of lightweight elements are
a. mercury, venus, earth, and neptune.
b. earth, saturn, neptune, and venus.
c. venus, saturn, uranus, and neptune.
d. jupiter, saturn, uranus, and neptune.

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.