Answer:
I don't see an O in the picture at all.
but here's how you solve it: just count the nodes between the species, the fewer the closer
I would go for E and I, only one step between them
Consecutive odd or even integers are of the form x, x+2.
So we have x(x+2) = 63, where Diane's age = x.
x²+2x = 63.
x² + 2x - 63 = 0
(x + 9)(x - 7) = 0
x = -9, or 7.
Since -9 is awfully young, we rule it out and say Diane's age is 7, and her sister is 9.
