B square times 6*(50) divided by %5, what is the answer??? b square is from Pythagorean thereon (10)

Katlyn made 4 dresses with 7 yards of fabric. how many yards did she use on 1 dress?

15 points ! ~ see if you know the answer to both you!

Factor the polynomial 4x4 – 20x2 – 3x2 + 15 by grouping. what is the resulting expression? (4x2 + 3)(x2 – 5) (4x2 – 3)(x2 – 5) (4x2 – 5)(x2 + 3) (4x2 + 5)(x2 – 3)