Andy has two similar conical hats, hat a and hat b. the diameter of hat a is 18 inches, and the diameter of hat b is 9 inches. what is the ratio of the volume of hat a to the volume of hat b?

2: 1
16: 1
4: 1
8: 1

i got 2: 1 but i don't think that is right. you!

Here is their argument. given the obtuse angle x, we make a quadrilateral abcd with ∠dab = x, and ∠abc = 90◦, and ad = bc. say the perpendicular bisector to dc meets the perpendicular bisector to ab at p. then pa = pb and pc = pd. so the triangles pad and pbc have equal sides and are congruent. thus ∠pad = ∠pbc. but pab is isosceles, hence ∠pab = ∠pba. subtracting, gives x = ∠pad−∠pab = ∠pbc −∠pba = 90◦. this is a preposterous conclusion – just where is the mistake in the "proof" and why does the argument break down there?

Ascatterplot is produced to compare the size of a school building to the number of students at that school who play an instrument. there are 12 data points, each representing a different school. the points are widely dispersed on the scatterplot without a pattern of grouping. which statement could be true

Write two subtraction equations that are equivalent to 5 + 12 = 17.