A:Answer 5ghz routers, will have a 2.4ghz radio as well.
This is called "Dual Band."
Even the integrated modem/router combo's the ISP provide are Dual Band.
2.4ghz works at a longer range than 5ghz, this is beneficial for a robot traversing the entire house!
It is better that it is 2.4ghz as opposed to 5ghz!