Answer 1

Light waves are electromagnetic waves while the sound waves are mechanical waves. Light waves do not require any material medium for their propagation while sound waves need the material medium for its travel from one place to another.
Due to the large magnitude of difference between the speed of light (i.e 3 X 10⁸ m/s) to the speed of sound in air (330 m/s) , the light reaches first and then the sound from the object. Like, in thunderstorms, the light reaches first to earth and then the person hears the sound of light.