Final answer:
The volume of water in the rectangular prism aquarium is 100.8 cubic feet.
Step-by-step explanation:
To find the volume of water in the rectangular prism aquarium, we multiply the length, width, and depth.
In this case, the length is 84 inches, the width is 36 inches, and the depth is 48 inches. So the volume is 84 x 36 x 48 = 144,192 cubic inches.
To convert this to cubic feet, we divide by 12 x 12 x 12, since there are 12 inches in a foot. So the volume in cubic feet is 144,192 / (12 x 12 x 12) = 100.8 cubic feet.