According to Rashi...
1. Why does Hashem count us all the time? (1:1)
2. If your father was from one tribe and your mother is from another, which tribe are you from? (1:2)
3. How did drafted soldiers demonstrate which tribe they were from? (1:18)
4. How were the colors of the tribal flags chosen? (2:2)
5. Why are Aharon's sons listed as the sons of Aharon and Moshe?