How many significant digits in 0.23100

There are 5 significant digits in 0.23100.

Explanation:

This is because all non-zero digits are considered significant and zeros after decimal points are considered significant.

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.