Based on what you learned about the evolution of star clusters, select all of the correct statements from the following list.
O The turnoff point is when stars in a cluster begin to no longer shine.
O All stars in a cluster are about the same age.
O Stars in globular clusters tend to be helium-poor.
O The less massive stars in a cluster leave the main sequence first.
O Open clusters have more stars than globular clusters.
O Stars in globular clusters tend to be older than those in open clusters.
O The age of a cluster can be determined by where the stars are leaving the main sequence.