Can someone answer theses 2 short questions? i’m in a hurry.

Aboat costs 19200 and decreases in value by 12% per year. how much will it cost in 5 years

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?

Find the vertex for the parabola given by the function ƒ(x) = −3x2 − 6x.