Answer:
Volume=  729 m³
Step-by-step explanation:
The volume is the space occupied by a thing.
The volume of the right angled  rectangular prism is given by
Volume= length * breadth* height
Since all the sides are equal  we can calculate the volume by
V= L*w*h
V= 9m*9m*9m = 729 m³
A rectangular prism looks like this.