please help. Sound travels at 330 m/s. If a lightning bolt strikes the ground 5 m away from you, how long will it take for the sound of the strike to reach you?

A12-g wad of sticky clay is hurled horizontally at a 100-g wooden block initially at rest on a horizontal surface. the clay sticks to the block. after impact, the block slides 7.5 m before coming to rest. if the coefficient of friction between the block and the surface is 0.65, what was the speed of the clay immediately before the impact?