What the study misses is that the participants Brazilians are likely to meat-eaters who were denied meet. Try run the study in places like India with partial vegetarians. If denied meat, they are not likely to have similar outcomes.
All of them still need plugins. This is just a plain user hack to include hashtags in the mail body itself. But thanks for all the interesting information. That said, I never believed it was any novel enough. Many must have thought about it earlier was my first thought.
While we are discussing service, I have fond memories of IBM's service for Thinkpad. I moved from US to India. Before I left, I had sent a Thinkpad for repair. They told me a repair vendor (Selectron I think) needs a replacement motherboard from Japan (no idea why so!). They promised it will be sent to India to me. I doubted that. They not only shipped it to India but also paid customs duty as Indian customs won't accept it as repair but levied duty as a new laptop!
Really miss the great IBM service.
Apple only wants to use India to sell its stuff, particularly old model goods. It has avoided for longest time to provide Apple service through its own stores. It uses reseller network that is not the same as having own stores and service. Now this is amazing that Apple won't accept returns in India when Apple goods bought via Amazon can be returned in India!
Calculus And Analytic Geometry
by Ross L. Finney and George B. Thomas
is a good introduction to basic calculus. I understand you want something covering everything in math. Courant is the best one and others have written about it a lot.
While others are recommending platforms to practice, here are my 2 cents. Most important asset for a public speaker is "clarity". Clarity of thoughts is a magnet for audience attention. Once you have an audience "connect", anything you say is gold. Clarity of thought can be improved by these two resource books:
1. Art of Argument - Giles St.Aubyn (ISBN 0800803698)
2. Influence - Robert Cialdini (006124189X)
After that, try reading some Bertrand Russell writings. See how your argument and persuasion quality jumps from above resources.
1. You study the wonderful Kerninghan & Richie book. It's a great work of art.
2. C's architecture is just raw computing. Try building a toy interpreter or compiler and you will know most of CS in bargain too!
Good luck my friend.