A $7\mathrm{.}5-$g bullet is fired into a $0\mathrm{.}5-$kg wood block, where it lodges. This causes the block to slide $6\mathrm{.}0$ m across the floor before coming to rest. If the coefficient of friction between thewood block and floor is u k $=0\mathrm{.}25,$ what was the bullet's speed? Show all work.