table: 1-11071897-1
columns: Interregnum began, Interregnum ended, Duration, Count Palatine of Saxony, Count Palatine of the Rhine
Q: What is the number of interregnum for duration 3 months, 6 days?
A: SELECT COUNT Interregnum ended FROM 1-11071897-1 WHERE Duration = '3 months, 6 days'