This reminds me of the story of a Birdseed B747 on approach to LHR.
ATC had, more than once, asked the B747 to reduce it's speed and the B747 had complied, when ATC once more asked the B747 to reduce it's speed the somewhat pompous reply came back, something to the effect, "My dear chap, are you aware of the stalling speed of a B747?" ... As quick as anything the controller replied "No sir, but if you ask your First Officer I'm sure that he'll be able to tell you"
