Here are the answers to your questions:
Question 1:
Ellos comen a las ocho.
Question 2:
Nosotros compartimos el arroz con leche.
Question 3:
The verb form you would use with ellos, ellas, or ustedes is: comparten.
Question 4:
Dinner (la cena) in the Spanish-speaking world is generally later compared to dinner in the U.S.
Question 5:
The most common rice dish in Spanish-speaking countries is arroz con pollo.