I need help.

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

Yoku is putting on sunscreen. he uses 2\text{ ml}2 ml to cover 50\text{ cm}^250 cm 2 of his skin. he wants to know how many milliliters of sunscreen (c)(c) he needs to cover 325\text{ cm}^2325 cm 2 of his skin. how many milliliters of sunscreen does yoku need to cover 325 \text{ cm}^2325 cm 2 of his skin?

Acomputer store bought a program at a cost of $10 and sold it for $13. find the percent markup