Josephine mixed Ambergris worth $5.50 per milligram with Byzantium worth $3.00 per milligram. How much of each did she use if her final 40 milligram mix cost $4.00 per milligram?

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