No, I am not a student looking for help with homework..
I am preparing for job interviews and as I was searching websites for interview questions, I came across a question paper from MIT.. One of the questions is the attached file.. Just brushing up my basics..
I don't think you can measure from unknown to unknown and report a mix/max timing. What the shaded area means is that either one of the signals can be high or low during this time. In other words these shaded timing areas are variables. Only the timings from known to known values are for certain.