Answer:
5670 cm^3 or 5670cm cubed
Step-by-step explanation:
Original sides-
12, 15, 18
After increasing by 3-
15, 18, 21
Finding the volume of a rectangular prism is length*width*height.
=15*18*21
=270*21
=5670
Therefore, the volume of the new prism is 5670cm cubed.
Hope this helped^^