At t1 = 2.00 s, the acceleration of a particle in counterclockwise circular motion is (6.00 m/s2) i + (4.00 m/s2) j. It moves at constant speed. At time t2 = 5.00 s, its acceleration is (4.00 m/s2) i + (– 6.00 m/s2) j. What is the radius of the path taken by the particle if t2 – t1 is less than one period?