First hint: how can you convert the numerical data from the X and Y axes into total number of events? (Need help? Hint 2.)

Once you can quantify the events in each plot: what is the total number of events? Of like-signed? Of unlike-signed? Then what must have been the muon quality determination made for the opposite-signed dataset: what was the cut made on the original set of 2000 events? So to the plot of which muon quality cut from our IPPW exercise should you compare the opposite-signed invariant mass plot in the e-Lab? What e-Lab tools would you need to replicate in the e-Lab all the histograms you've produced in this IPPW exercise? What other tools might you like to have in the e-Lab, then, and why?