Which has more mass, a cup of water, a metal block, or a rock?

The metal block has the most mass

Explanation:

The metal block.

Explanation:

Assuming they are all the same size, if you picked put the three on a scale, you will see that the metal block is the most heavy.

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.