Input question: In mathematics, which letter of the alphabet is given to the imaginary number equal to the square root of -1?

Output answer: letter i

Input question: Since the start of the present ice age about 2.5 million years ago at least how many severe glacial periods have there been?

Output answer: 17

Input question: If women are XX, what are men?

Output answer: xy

Input question: Her 2009 album is called 'Quiet Nights', so which Canadian jazz singer and pianist is married to Elvis Costello?

Output answer:
diana krall