[填空题]
A 25-g bullet strikes and becomepl r(fwf6ygcvewf7 6 syu()7,s:r4m; ab fme+p embedded in a 1.35-kg block of wood placed on a horizontal surface just in front of the gun. If the coefficient of kinetic friction between the block and the surface is 0.25, and the impact drives the block a distance offp;r :+4emmb a 9.5 m before it comes to rest, what was the muzzle speed of the bullet? m/s