At the market 5 light bulbs costs $9 how much do 7 light bulbs cost

Idon’t understand this.. will someone ? will mark brainliest along with 20 points.

Ingredient c: 1/4 cup for 2/3 serving or ingredient d: 1/3 cup for 3/4 serving which unit rate is smaller

Find the equation of the ellipse with the following properties. the ellipse with foci at (0, 6) and (0, -6); y-intercepts (0, 8) and (0, -8).edit: the answer is x^2 over 28 + y^2 over 64 = 1