Answer this question: how many presidents have been assassinated?
----
Answer: Four sitting presidents have been killed: Abraham Lincoln (the 16th President), James A. Garfield (the 20th President), William McKinley (the 25th President) and John F. Kennedy (the 35th President).

Answer this question: who is the group enigma?
----
Answer: Enigma is an electronic musical project founded in Germany by Michael Cretu , David Fairstein and Frank Peterson in 1990.

Answer this question: what makes a dwarf planet?
----
Answer:
More explicitly, the International Astronomical Union (IAU) defines a dwarf planet as a celestial body in direct orbit of the Sun that is massive enough for its shape to be controlled by gravitation , but that unlike a planet has not cleared its orbital region of other objects.