17 N
42 N
25 N
25 N
Net force:

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.

just did the assignment and the answer was #1 +2 n

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.