The Answer is the first one
Answer:
21
Step-by-step explanation:
Answer:A
Step-by-step explanation:
Answer:
9 inches.
Step-by-step explanation:
Fun question! The length of a space diagonal for a cube is ![\sqrt{3*sidelength^2}](https://tex.z-dn.net/?f=%5Csqrt%7B3%2Asidelength%5E2%7D)
Thus, the first cube has a side diagonal of ![\sqrt{3}](https://tex.z-dn.net/?f=%5Csqrt%7B3%7D)
The next cube would have a side diagonal of 3
The third cube would have a side diagonal of ![3\sqrt{3}](https://tex.z-dn.net/?f=3%5Csqrt%7B3%7D)
And the fourth cube would have a side diagonal of 9.
Since the fifth cube has a side length equal to the side diagonal of the fourth cube, it should be 9 inches.