So firstly, you're gonna replace the T variable with 2.2, which is the time given to us. And so the equation is gonna look like this:
![2.2=2*3.14* \sqrt{ (L)/(32) }](https://img.qammunity.org/2019/formulas/mathematics/middle-school/2uxx13381k2jh3ml0was9qzlstd2rw2pun.png)
and we will be solving for L.
The next thing you wanna do multiply 2 and 3.14 together, so your equation should look like this:
![2.2=6.28* \sqrt{ (L)/(32) }](https://img.qammunity.org/2019/formulas/mathematics/middle-school/6fyno61317qg2nvqnmvrwipf8je7klswtg.png)
After that, you're gonna want to square all the terms in this equation (2.2, 6.28, and
![\sqrt{ (L)/(32) }](https://img.qammunity.org/2019/formulas/mathematics/middle-school/3bofpzzy85xc8m19wlfra63gihyckf3fi4.png)
) to remove the square root. Your equation will look like this
![4.84=39.4384* (L)/(32)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/5fy7c7g17gsdcnm4na1ltfjeyzzh3k75q5.png)
Next up is you're gonna multiply 32, the reciprocal of 1/32, on each side so that the equation looks like this
![154.88=39.4384*L](https://img.qammunity.org/2019/formulas/mathematics/middle-school/ahxgbrtn67is5adiv8ri85hhvq1vxqvwrk.png)
After, you're gonna divide 39.4384 on each side, and your equation should end up at
![3.927=L](https://img.qammunity.org/2019/formulas/mathematics/middle-school/2nzp7qyoc9e95dieovniou79w4bepqzzhw.png)
. And assuming from your options, they are gonna want you to round to the nearest whole number, so the best option is 4 feet.