What position does O hold in the English alphabet?
Answer15th
Counting A as 1, O is the 15th of the 26 letters.
Language · Facts & stats
O facts & stats
7 fact-checked facts about the letter O, each with the reason behind it. 5 more are in today's round and join this page after it closes.
The basics
Which blood type has neither A nor B antigens on its red blood cells?
AnswerType O
Type O red cells carry neither the A nor the B antigen.
Going deeper
What is the chemical formula for ozone?
AnswerO3
Ozone is a molecule of three oxygen atoms, while the oxygen we breathe is O2.
In Big O notation, what does O(n) describe?
AnswerWork that grows in proportion to input size
O(n) means linear growth: double the input and the work roughly doubles.
On a standard QWERTY keyboard, the O key sits between which two letters?
AnswerI and P
The top letter row reads Q W E R T Y U I O P.
Expert level
How is the letter O sent in Morse code?
AnswerThree dashes
O is dash-dash-dash; S is dot-dot-dot, so SOS is ... --- ...
About what percentage of Earth's atmosphere by volume is oxygen?
Answer21%
Dry air is about 78% nitrogen and about 21% oxygen.
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