Write (1+3i)3 in simplest a+bi form

In a class, there are 12 girls. if the ratio of boys to girls is 5: 4 how many boys are there in the class

Mandy and four of her friends want to see a movie. if m represents the cost for one person to see a movie, which expression represents the cost for mandy and her friends to see a movie?

Draw and label the figure described. mn and pq intersecting at point r.