Question: Petras Jonaitis Mantigirdaitis, was a prominent noble of the Grand Duchy of Lithuania. in 494, Mantigirdaitis was sent on the diplomatic mission to negotiate peace with the Grand Duchy of Moscow and marriage of Helena of Moscow to where?
{'answer': 'Alexander', 'supporting_facts': [['Petras Jonaitis Mantigirdaitis', 1], ['Petras Jonaitis Mantigirdaitis', 2], ['Petras Jonaitis Mantigirdaitis', 3], ['Petras Jonaitis Mantigirdaitis', 4], ['Helena of Moscow', 0], ['Helena of Moscow', 1], ['Helena of Moscow', 2]]}