I really don't get pH curves. I have to sketch a pH curve for the titration of 40.00 mL of 0.100 M hydrazine, H2NNH2(aq) having a Kb of 3.0x10^-6 by 0.100M HCIO4(aq). I know you can't sketch on here. But can you help me find the first point?

I know its a (SA-WB)

I answered this at your post several pages earlier.