If gear A rotates with a constant angular acceleration of A=90rad/s2, starting from rest, determine the time required for gear D to attain an angular velocity of 600rpm. Gears A,B,C, and D have radii of 15mm,50 mm,25mm, and 75mm, respectively. Express your answer to three significant figures and include the appropriate units. What time is required? Express your answer to three significant figures and include the appropriate units