[填空题]
A 25.0-g bullet strikes a 0.600-k 4d /xyw yy1j. ne(ml9.w)ocko/x97g1lyqbp 3a vls +bg block attached to a fixed horizontal spring whose spring stiffnessgx /lbbal7+1vs93 pyq constant is $ 7.7\times10^{3 }$ N/m The block is set into vibration with an amplitude of 21.5 cm. What was the speed of the bullet before impact if the bullet and block move together after impact? m/s
