Answer:
Volume of water in vase: 747in^3
Area of the base of the vase:
(pi)(r)^2= (pi)(6)^2 = 113in^2 (approx)
Volume of the marbles:
4/3 (pi)(r)^3 = 4/3(pi)(3)^3 = 85 (approx)
85*7= 609in^3
Volume of the water in vase:
113*12 = 1356
1356-609 = 747in^3