Multi 21 was a code for car 2 (Mark Webber) to finish ahead of car 1 (Seb Vettel). Vettel ignored that message and overtook Webber to win. That is why Webber said Multi 21 to Vettel because the order had come in to stay in the positions they were in.
Multi 33 should have been Multi 333 because Ricciardo is car 3 and Verstappen is car 33.
Just so you know, GP2 and GP3 will not be in Austin. They generally only run in Europe and a few other rounds like Bahrain and Abu Dhabi. GP3 currently doesn't run in Monaco but will be running in Malaysia for the first time, as well as GP2.
GP2 and GP3 are pretty interesting if you want to see future F1 drivers. Bottas, Ocon, Kvyat and Gutierrez all won the GP3 series and GP2 has a few notable champions like Hamilton, Rosberg, the UnStoffable Stoffel Vandoorne and your friend and mine, Pastor Maldonado.
I watch far too much motorsport and I'm one of the crazy ones that watch the practice sessions for F1. I think this will be my 24th full season of watching F1. Indycar also starts up this week and Nascar has been back for the last few weeks. There is also a Formula E race this week.
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