8. A 0.245 kg plastic ball is tied to 1 end of a 0.98 m long string and is swung in a horizontal circle. If it takes 1.05 s to complete 1 circle, what is the speed of the ball?
O v = 4.11
O v = 3.36 m
O v = 6.56 m
O v= 5.86 m
None of these is correct.