Title: Beyonce.
Question: What was the name of Beyonce's tour that she started on April 15?

Title: Armenia.
Question: How many people died as a result of the MVD and NAA clash in 1918?

Title: Vacuum.
Question: Al-Farabi concluded a perfect vacuum was incoherent using what?

Title: Ottoman Empire.
Question:
What did the Treaty of Balta Liman do for Ottoman markets?