Astronomers can measure it by way of luminosity which is the power of a star or the amount of energy (light) the star admits from its surface. they also measure the brightness of a start as if it were to appear 32.6 light years from Earth
Viruses are not classified as being alive in because of the fact that they can't reproduce.
Molarmass of beryllium is 9.0
molar mass of silicon is 28.4
molar mass of calcium is 40.1
molar mass of rhodium is 103.