Which power of 2 is equal to this expression: (2•2•2)-2

Can you me find the missing length. i attached an image.

Assume that y varies inversely with x. if y=1.6 when x=0.5 find x when y=3.2 acellus answer

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?