To solve this problem you must apply the proccedure shown below:
1- You must rewrite each value shown in the picture attached, in decimal form, as following:
6π-6=12.84
π^3=31
√99=9.94
2- Now, you can order the values from least to greatest:
√99
6π-6
π^3
The answer is:
√99
6π-6
π^3