Anybody doing anything important is often called upon to explain himself. Here's how.
Andrii Sedniev is a force to be reckoned with. At the tender age of 24 he has mastered dance, karate, mathematics, CISCO technology, and public speaking. I am sure that other talents to be disclosed casually, like "by the way, on my way to winning the America's cup" or something equally offhand.
We in Toastmasters are randomly called upon every week to deliver impromptu speeches, called "Table Topics." The classic notion, dating back to the Greeks, is that a public person should be ready to hold forth on almost any topic at a moment's notice. More specifically, an executive should be able to articulate and defend his positions, a salesman promote his product, and a politician argue his policies for any audience, anywhere.
Though Sedniev does not frequently reference his prior work, "The Magic of Public Speaking," there is an obvious continuity in the themes. Just like a martial artist, the speaker has to be up for the game - enthusiastic. He has to be prepared. He has to have a repertoire of stories which he can tell on a moment's notice, and the ability to segue smoothly from the question being asked to the answer he is prepared to give.
There is quite a bit of advice which is specific to short speeches, what would amount to the answers one might provide an interviewer. Open strongly, if possible taking the conversation in an unanticipated direction. This provides interest and gives you control. Make one solid point, which is all one can hope for in two or three minutes. Make a short, punchy conclusion, if possible wrapping back to the introduction.
This review hits only the highlights; the book takes an hour or two to read, and presents its points in a memorable fashion. While Toastmasters will immediately recognize its utility, I would recommend it to anybody who is called upon frequently to speak in public.
NB: Sedniev talks about mastering mathematics as one of his early-life challenges. He says that he spent a few months figuring out the sum of the infinite series of inverse squares: 1/1^2+1 /2^2+1/3^2..... I can believe that he did. This is a classic problem in mathematics , called the Basel problem, posed in 1644 and solved by the famous Euler almost a century later. It requires a considerable knowledge of number theory. The answer, BTW, is pi^2/6.