Answer:
The answer is option 2.
Step-by-step explanation:
It is given that the formula of the volume of rectangular prism is, V = length×width×height. Then you have to substitute the values into the formula to find the volume :
length = 3x
width = 7x
height = 15x
V = (3x) × (7x) × (15x)
= 315x³
