Answer:
If Franco wants to double the volume, he must multiply the radius and height of the original cone by 
![\sqrt[3]{2}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/j4130101zt2ln52rf0gqhfk0z0n7mvjr0h.png)
Explanation:
we know that
If two figures are similar, then the ratio of its volumes is equal to the scale factor elevated to the cube
Let
z-----> the scale factor
x----> the volume of the larger cone
y----> the volume of the original cone
so

we have


substitute and solve for the scale factor

![z=\sqrt[3]{2}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/c4imcwv7qltnj4r3cw2y0y0c6ehonut7jp.png) ------> the scale factor
 ------> the scale factor
If Franco wants to double the volume, he must multiply the radius and height of the original cone by 
![\sqrt[3]{2}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/j4130101zt2ln52rf0gqhfk0z0n7mvjr0h.png)