Mensa - 75th Anniversary - First Day Cover

Some of our family visited this morning. Then after lunch I attended a Mensa Cambridge Zoom meeting. I also watched the Formula One qualifying.

Today's picture is of a Mensa First Day Cover for Mensa's 75th Anniversary. I used to collect first day covers and have quite a collection, but these days only collect a few special ones. I have not attempted to solve the puzzles yet. The answers are provided in the envelope, but I have not cheated and looked at them.

The temperature at GMT today was sixteen degrees Celsius.