[填空题]
A 0.060-kg tennis ball, moving with a speed of ,:mt( kjf (6jno mz6fl2.5m/s collidwcgb wo+ f7bpuo)/ 7v;es head-on with a 0.090-kg ball initially moving away from it at a speed of 1 b/wg uwo;o+c )7bpfv7.15m/s Assuming a perfectly elastic collision, what are the speed and direction of each ball after the collision?(Let A represent the 0.060-kg tennis ball, and let B represent the 0.090-kg ball.)v'$_A$ = m/s v'$_B$ = m/s