1. Yes. to calculate the volume of a sphere you do [tex] \frac{4}{3} \pi r^{3} [/tex], with a radius of 4, you get ≈268.08. then you have to calculate the volume of the cube, which is length x width x height, so you get ≈421.88. 421>268, so JD is correct
2. you need to find out how much weight a balloon with a diameter of one foot can hold, so you divide 8 by 8 to get one, and 17 by eight to get 2.125. You multiply that by 136 to get 289. The balloon would have to be 289 diameters to hold a 136 pound person.
Hope this helps :)
