Final answer:
The speed of sound in helium at 100°C would be greater than the speed of sound in air at 20.0°C, which is 343 m/s, because helium is lighter and the temperature increase would cause higher particle kinetic energy, thus faster sound speed.
Step-by-step explanation:
The speed of sound in gases is indeed temperature-dependent and can be calculated using the ideal gas law and principles of wave mechanics. However, the direct answer concerning the speed of sound in helium at the boiling temperature of water (100°C) is not provided in the reference information you've given. Nonetheless, we can infer that because sound travels faster in lighter gases and helium is lighter than air, the speed of sound in helium would be greater than the speed of sound in air, which is 343 m/s at 20.0°C. As temperature increases, the speed of sound also increases due to the increase in kinetic energy of the gas particles.