Here's a short story:

16:9 (1.7:1) (16:9 = 4:3) is an aspect ratio with a width of 16 units and height of 9. Since 2010 it has become the most common aspect ratio for televisions and computer monitors, and is also the international standard format of HDTV, Full HD, non-HD digital television and analog widescreen television. This has replaced the old . 

Dr. Kerns H. Powers, a member of the SMPTE Working Group on High-Definition Electronic Production, first proposed the 16:9 (1.7:1) aspect ratio at a time when nobody was creating 16:9 videos. The popular choices in 1980 were: 1.3:1 (based on television standard's ratio at the time), 1.6:1 (the European "flat" ratio), 1.85:1 (the American "flat" ratio), 2.20:1 (the ratio of 70 mm films and Panavision) and 2.39:1 (the CinemaScope ratio for anamorphic widescreen films). 

Powers cut out rectangles with equal areas, shaped to match each of the popular aspect ratios. When overlapped with their center points aligned, he found that all of those aspect ratio rectangles fit within an outer rectangle with an aspect ratio of 1.7:1 and all of them also covered a smaller common inner rectangle with the same aspect ratio 1.7:1. The value found by Powers is exactly the geometric mean of the extreme aspect ratios, 4:3 (1.3:1) and 2.35:1 (or 64:27, see also for more information), √ ≈ 1.770 which is coincidentally close to 16:9 (1.7:1). Applying the same geometric mean technique to 16:9 and 4:3 yields the aspect ratio, which is likewise used as a compromise between these ratios. (End of story)

Provide your best guess for the following question. Give ONLY the guess, no other words or explanation.

For example:

Guess: <most likely guess, as short as possible; not a complete sentence, just the guess!>

Here are a few examples of questions and answers:

Question: What is the most common aspect ratio for TVs?
Guess: 16:9 = 4:3) is an aspect ratio with a width of 16 units and height of 9. Since 2010 it has become the most common aspect ratio for televisions and computer monitors

Question: Is this the international standard?
Guess: yes

Question: For which types of TV?
Guess: HDTV

Question: And?
Guess: Full HD

Question: Anything else?
Guess: non-HD digital television and analog widescreen television

Question: Who proposed this ratio?
Guess: Kerns H. Powers

Now answer the following question in the same format.

Question: Is he a doctor?

yes