66 because you divide 100 by 90 that multiply that number by 60
The volume is the product of the height and the area of the base.
V = Bh
The area of the square base is (4 cm)² = 16 cm², so the height can be found from
144 cm³ = (16 cm²)h
h = (144 cm³)/(16 cm² = 9 cm
The height of the prism is 9 cm.
True, and it's called an isosceles right triangle :D

has y = 0 as a solution.
Selection B is appropriate.
The median is the one in the middle. Sorting the data gives
$1.61, $1.75, $1.79, $1.84, $1.96, $2.09, $2.11
Seven data points and the fourth one is 1.84.
Answer: $1.84