What type of units are used to describe volume?

Which equation represents the partial sum of the geometric series?

Aline passes through 3,7 and 6,9 what equation represents the line

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?