Answer
It weighs 4302 pounds; the thief would be unable to walk away with the gold sphere.
Work Step by Step
First, you need to calculate the volume of the sphere, which using the equation $V = (4/3)*pi*r^{3}$, with $r$ as 28.9 centimeters gives you approximately 101107.2 cubic centimeters. Multiplying this volume by the density of gold in $g/cm^{3}$ gives a mass of 1951369 grams, or approximately 1951.4 kilograms. Multiplying this value by the conversion constant of 2.20462 pounds/kilogram gives you a weight in pounds of about 4302 pounds, which is far more than anyone could lift unassisted.
