Answer: look at the explanation and try to work it
Explanation: in contrast, our atmosphere blocks most ultraviolet light (UV) and all X-rays and gamma-rays from reaching the surface of Earth. Because of this, astronomers can only study these kinds of light using detectors mounted on weather balloons, in rockets, or in Earth-orbiting satellites.
In both cases, that is the mass of 6.02 × 1023 representative particles. The representative particle of CO2 is the molecule, while for Na2S, it is the formula unit.