The ozone layer protects living things on earth from

The ozone layer acts as a filter for the shorter wavelength and highly hazardous ultraviolet radiation (UVR) from the sun, protecting life on Earth from its potentially harmful effects. When the sky is clear, there is an inverse relationship between stratospheric ozone and solar UVR measured at the Earth's surface.

Hope that helped :)

1) clean up you lab area2) dispose of the chemicals as instructed by your teacher3) put everything back where it belongs unless your teacher tells you otherwise4) dispose of gloves5) wash hands with soap and water

As what he you go get the hot dog ; )