$abcd$ is a square. how many squares have two or more vertices in the set $\{a, b, c, d\}$?

There are 4 squares having a side corresponding to a side of square abcd.

There are 4 squares having a side corresponding to the diagonals of square abcd.

And then the original square

Therefore, there are 4 + 4 + 1 = 9 squares having two or more vertices in the set {a, b, c, d}.

12 oz: $0.35 per oz

16.3 oz: $0.38 per oz

28 oz: $0.30 per oz

64 oz: $0.33 per oz

Which size is the best deal?

28 oz

Step-by-step explanation: it gave me the right answer after.