Answer
$4.308Km/s$
Work Step by Step
We can find the required speed as follows:
$v=\sqrt{\frac{5KT}{m}}$
We plug in the known values to obtain:
$v=\sqrt{\frac{5(1.38\times 10^{-23}J/K)(450K)}{(1.008)(1.66\times 10^{-27}Kg)}}$
$v=4.308\times 10^3m/s=4.308Km/s$
