Answer
$20m$
Work Step by Step
We can determine the required height as follows:
$h=\frac{\frac{5}{2}k_BT}{mg}$
We plug in the known values to obtain:
$h=\frac{\frac{5}{2}\times 1.38\times 10^{-23}\times 300}{5.31\times 10^{-23}\times 9.8}$
This simplifies to:
$h=20m$
