Which is the equation of an ellipse with directrices at x = ±4 and foci at (2, 0) and (−2, 0)?

Ebuka's monthly rent is $750. if ebuka pays the rent late, his landlord charges 4% interest per week that the payment is late. write a function that gives the total cost r(t), in dollars, of ebuka's rent if he pays it t weeks late.