In which two types of reactions do opposite chemical changes occur? double replacement and combustion
single replacement and double replacement
synthesis and decomposition
combustion and synthesis

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.