The sum two numbers: 152.50 and 2.462
Reported to the correct number of significant figures is

5 and 4

Explanation:

All numeral digits are important for sig figs and any zeros inbetween.  Any zeros after are seen as important in decimals but not before.

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.

14 days is the half-life of phosphorus-32