Biker/Turning of pedals/Comparison/Exercise

Two bicyclists, ${}A$ and ${}B$, drive on their bikes along a street. ${}A$ makes ${}40$ pedal turnings per minute, has a gear ratio of pedal to back wheel of ${}1$ to ${}6$ and tyres with a radius of ${}39$ centimeter. ${}B$ needs ${}2$ seconds for one pedal turning, has a gear ratio of pedal to back wheel of ${}1$ to ${}7$ and tyres with a radius of ${}45$ centimeter.

Who is driving faster?

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