The first periodic table of elements Mendeleev created contained only 70 elements. True or false?

True or false graphs must include scales that increase by the same amount

Compare the horizontal displacement of the two balls as they travel to the ground. what do you observe?

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.