A light wave can travel

Light waves can travel in vacuum but sound waves require a material medium. Why?

A light wave is travelling along - Y direction. For this light wave, which of the following equations of planes may represent its wavefront.

Why can light waves travel in vacuum whereas sound wave cannot?

When a light wave travels from air to glass,

When a light wave travels from air to glass :

Statement 1: Sound waves can not propagate through vacuum but light waves can. Statement 2: Sound wave can not be polarised but light waves can be.