Answer:
The scale factor is 3 : 1.
Explanation:
We know that,
The scale factor of the dilation of a prism is the cube root of the ratio of the volume of resultant prism after dilation and the volume of the given prism,
Here, the volume of prism before dilation = 20 cube unit,
And, the volume of the prism after dilation = 540 cube unit,
Thus, by the above statement,
![\text{The scale factor of dilation}=\sqrt[3]{(540)/(20)}](https://img.qammunity.org/2017/formulas/mathematics/high-school/en8odrdw80b3ou16fhkijiklbb8zedm5qy.png)
![=\sqrt[3]{27}](https://img.qammunity.org/2017/formulas/mathematics/high-school/ufk48uacyvj6blete3b9llpbab4ixf3olk.png)

Hence, the scale factor is 3 : 1.