a. volume of the stage in the banquet hall = 22 x 15 x 4 = 1,320 cubic foot.
weight of the stage in the banquet hall:
1 cubic foot weighs 62.4 pounds
1,320 cubic feet will weigh 1,320 x 62.4 = 82,368 pounds.
b. volume of each cylindrical pillar = pi * r^2 * h = pi * (1/2)^2 * 9 = pi * 1/4 * 9 = 7.069 cubic feet
weight of each cylindrical pillar:
1 cubic foot weighs 62.4 pounds
7.069 cubic feet will weigh 7.069 x 62.4 = 441 cubic feet.