The multi-national Communist armed forces' sole joint action was the Warsaw Pact invasion of Czechoslovakia in August 1968. All member countries, with the exception of the Socialist Republic of Romania and the People's Republic of Albania participated in the invasion.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): In which year was the Warsaw Pact activated in a joint action?
Ah, so.. 1968

Important geological concepts were established as naturalists began studying the rock formations of the Alps in the 18th century. In the mid-19th century the now defunct theory of geosynclines was used to explain the presence of "folded" mountain chains but by the mid-20th century the theory of plate tectonics became widely accepted.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Who began studying the rock formations of the Alps
Ah, so.. naturalists

The Carnival continued its evolution in small/unimportant towns out of view of the rulers. The result was the uninterrupted celebration of Carnival festivals in Barranquilla (see Barranquilla's Carnival) now recognized as one of the Masterpieces of the Oral and Intangible Heritage of Humanity. The Barranquilla Carnival includes several parades on Friday and Saturday nights beginning on 11 January and ending with a six-day non-stop festival, beginning the Wednesday prior to Ash Wednesday and ending Tuesday midnight. Other celebrations occur in villages along the lower Magdalena River in northern Colombia, and in Pasto, Nariño (see Blacks and Whites' Carnival) in the south of the country. In the early 20th century, attempts to introduce Carnival in Bogotá were rejected by the government. The Bogotá Carnival was renewed in the 21st century.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Where did the Carnival gestate out of the purview of rules?
Ah, so..
in small/unimportant towns