The total weight in the container is 15.75lb
How to find the total weight?
The volume of a right rectangular prism is equal to the product between the 3 dimensions, so the volume of the container is:
V = 2.5ft*9ft*5ft = 112.5 ft³
We know that the mass per cubic foot is 0.14 lb, then the weight will be:
W = 0.14lb*112.5 ft³ = 15.75lb