A ___________ generally contains well over 1000 galaxies and is quite dense. They often contain many giant elliptical galaxies.
a. local group
b. poor cluster
c. rich cluster
d. tidal tail
e. quasar
Question 2
T Tauri stars are believed to be young, high-mass main-sequence stars.
a. True
b. False
Indicate whether the statement is true or false