Could somebody please help me??

Sophia wrote an equation to represent the revenue of a movie theater for one day. she let x represent the number of child tickets sold and y represents the nunver of adult tickets sold. if a child ticket cost $4, an adult ticket cost $6, and the total revenue for the daybwas $420, which equation could sophia use to represent the number of chikd and adult tickets that were sold?

Which of the following is most likely the next step in the series

What is the volume if this rectangular prism: 5/2 cm by 3/4 cm by 1/3 cm