13. A hole is drilled in a block of wood as shown in the sketch. The hole is 3/4 of the total depth of the wood. The total depth of the block of wood is 13/16 in.
How deep is the hole?
Hole

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.