From the given data, the angular acceleration of the wheel is
= = 24.76 .
Hence, linear acceleration is a = = = 8.047 m/s^2, where "r" is the radius.
In t = 4 seconds, the top speed is a*t = 8.047*2 = 16.094 m/s. ANSWER
Solved, answered and explained.
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On relations between the torque and moment of inertia, in popular form for beginners, see this Internet source