Generate a correct and concise answer for the question based on the words in the context.

[Q]: Context : The Sinclair Scientific calculator was a 12-function, pocket-sized scientific calculator introduced in 1974, dramatically undercutting in price other calculators available at the time. 
Question : In which year was the service entry date for Sinclair Scientific?
[A]: 1974


[Q]: Context : The GCR Class 1 was a class of steam locomotives designed by John G. Robinson for the Great Central Railway, and introduced to service between December 1912 and 1913. 
Question : What was the year that GCR Class 1 entered service?
[A]: December 1912


[Q]: Context : Jeanette, Lady Randolph Churchill, CI DStJ (née Jerome; 9 January 1854 -- 29 June 1921) was an American-born British socialite, the wife of Lord Randolph Churchill and the mother of British Prime Minister Sir Winston Churchill. 
Question : What is Lady Randolph Churchill's spouse's name?
[A]:
Lord Randolph Churchill