Root mean speed(rms) is the measure of the speed of the particle in a gas. it is square root of the velocity squared of the molecules in a gas.
that is rms= square root of ( 3RT/M)
R= gas constant(8.314)
T=temperature
M=mass(0.028kg)
rms is therefore square root of [ 3x 8.314 x(34.3+273)] /0.028kg
rms =523.20m/s