Answer:
contains many young stars
Explanation:
Irregular galaxies have <em>no definite shape</em>, which means that the first option is incorrect. They are definitely not round.
However,<u> they contain many young stars because the degree of star formation is fast.</u> They also contain old stars. Thus, the second choice is correct.
The "spiral galaxy" is the type of galaxy that has arms that extend from the center. These arms look "spiral," which influenced its name. This makes the last choice incorrect.
They are actually <u>smaller than the other types of galaxies.</u> This makes them <em>prone to collisions</em>. This makes the last choice incorrect.
Answer:
The period of a wave is the time for a particle on a medium to make one complete vibrational cycle. Period, being a time, is measured in units of time such as seconds, hours, days or years. The period of orbit for the Earth around the Sun is approximately 365 days; it takes 365 days for the Earth to complete a cycle.
There is no <span>radioactive decay</span>
The acceleration is 3 m/s per minute, or 0.05 m/s per second.
