$13.$ True or False: Radial engines are simpler to balance than inline engines due to their symmetrical layout.

$14.$ True or False: The mass$-$radius product is irrelevant in the calculation of balancing requirements for rotating machines.

$15.$ True or False: High$-$speed rotors always require dynamic rather than static balancing to ensure smooth operation.

$16.$ True or False: Torsional vibrations can be effectively reduced by adjusting the alignment of the drive shaft.