Which of the following forces causes comets to regularly return to the inner solar system after being gone for many years? A. friction
B. magnetism
C. electromagnetic force
D. gravity

answer carbon and three oxygen atoms;

sup bro, im dumb, but this is what i found xd

"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"