# Readout using an NMR spectrum

I'm trying to understand how to read results from an NMR quantum computer.

According to Nielsen and Chuang:

The principal output is the free induction decay signal $$V(t) = V_0\text{Tr}\left[e^{-iHt}\rho e^{iHt}(iX_k+Y_k)\right]$$

This signal is measured for some period of time, and then the results are Fourier-transformed into a plot like this one

My question is: what do these peaks mean? Suppose I want to know how much of my ensemble is in the $$|110\rangle$$ (or whatever) state, how do I read this off of the plot?