It is all public knowledge. 100 Senators and what 430ish House Members?
Just curious why?
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"Just curious why?"
Not sure what your question is directed towards, but I will answer both as best as I can.
Why if meaning why do we need this info: Not sure why he wants it. I'm guessing so he can send them info in regards to what the FDA is trying to do.
Why if meaning why so many representatives: I don't know