A person is riding a bicycle, and its wheels have an angular velocity of 29.9 rad/s. Then, the brakes are applied and the bike is brought to a uniform stop. During braking, the linear displacement of each wheel is 9.1 m. What is the magnitude angular acceleration (in rad /s2) of each wheel, if the radius of each wheel is 0.6 m ? Answer to 3 sig figs.