The clues are the ruler with the 1.6 mark and the multiplicity of spirals in her office.
You can ask her about the spirals, she will talk about the Golden Ratio, also known as Phi.
In her sketchbook on the table on the bottom of the room, you'll find a note that gives you the last information you need ⋅w⋅
I know noilol1 already answered, but in case you wondered how you're meant to find about it, here it is ^w^