Starburst galaxies:
contain a large number of very young stars, but very little evidence of gas clouds.
contain a large number of very old stars and almost no gas or dust.
are often associated with a galaxy that is colliding with another galaxy.
are common in rich clusters.
are composed of filaments and voids.

are often associated with a galaxy that is colliding with another galaxy.

Explanation:

A starburst galaxy is a galaxy that undergoes very fast formation of stars. The rate at which stars are born is 100 times more than 3 solar masses per year of the Milky Way. The starburst is stage of the formation of a galaxy. After this stage is complete the stars will have used almost all the gas in it. As the star formation rate is very fast the difference between the age of the stars and the galaxy itself is very less. The star formation is triggered by mergers and tidal interactions between gas-rich galaxies.

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