Debbie was doing a science lab, and she was instructed to decide whether a piece of plastic would float or sink without actually putting the plastic in the water. how could she do this? a. this is not possible. b. find the density of the plastic and compare it to the density of water c. find the volume of the plastic and compare it to the density of water d. find the mass of the plastic and compare it to the mass of a beaker of water

The answer is B, or "find the density of the plastic and compare it to the density of water"

Distance covered, s = 8ft - 4ft = 4 ftinitial velocity, u = 34 ft/sthe acrobat is moving upwards and therefore, a = -g = -9.81 m/s^2 = 32.19 ft/s^2applying equation of motion; s = ut -1/2gt^2then,4 = 34t -1/2*32.19t^24 = 34t - 16.095t^2rearranging; -16.095t^2 + 34t - 4 = 0solving the quadratic equation; t = {-34 +/- sqrt [34^2 - 4(-16.)]}/2(-16.095) = 1.06 +/- 0.93 = 0.13 or 1.99the acrobat will take 0.13 seconds to be at 8 ft above the ground. additionally, once at the maximum height, the acrobat will move down and be at the same spot (that is height) after 1.99 seconds moving down.