Which of the following is a drawback of using type Ia supernovae for measuring the distance of galaxies?
A) They are not bright enough to be noticed.
B) They cannot be calibrated.
C) They are a rare occurrence.
D) They occur only in spiral galaxies.
Question 2
The Local Group is a _____.
A) rich galaxy cluster
B) poor galaxy cluster
C) regular galaxy cluster
D) spherical galaxy cluster