What are three properties of components of the universe that can be determined using electromagnetic radiation?

Three properties of components of the universe that can be determined using electromagnetic radiation are temperature, chemical composition, and velocity. The temperature of celestial objects can be inferred from the peak wavelength of their emitted radiation, as described by Wien's Law. The chemical composition is revealed through spectral lines, which indicate the presence of specific elements. Additionally, the Doppler effect allows astronomers to measure the velocity of objects by observing shifts in the wavelength of their emitted light.