Aboy is pushing on a heavy door, trying to slide it open. his friend stands behind him and him push. how have the forces changed? a. the net force applied will increase. b. the net force will decrease. c. there will be less friction. d. the applied force will not change.

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.