How does and objects density determine whether the object will sink or float

If the speed of a particle triples ,by what factor does its kinetic energy increase?

According to newtons universal law of gravitation, which would change the parh of the ball so it traces out widest curved path possible?

Light that is polarized along the vertical direction is incident on a sheet of polarizing material. only 96% of the intensity of the light passes through the sheet and strikes a second sheet of polarizing material. no light passes through the second sheet. what angle does the transmission axis of the second sheet make with the vertical?