All over the world.
The first day of Passover in 1836 was April 2nd.
Passover occurred in April 2016 from April 22nd to April 30th.
Officially it was the year after they left Egypt, but it wasn't celebrated.
Yes, they absolutely can. Since passover is seven days (or eight in the diaspora) it must occur at least once.
It was part of the Exodus from Egypt and was commanded by God. See Exodus ch.12.
In 2010, Easter Sunday was the 6th day of Passover. Those often seem to occur close to one another. Wonder why that is.
Shevuos is about six weeks after Passover. If Lag BaOmer counts, then about two weeks after Passover is Lag BaOmer.
49 The seventh Sunday after Easter, commemorating the descent of the Holy Spirit upon the disciples.
Ishtar is a pagan fertility goddess whose rites occur in Spring, close to Passover. While the "holidays" were combined by the Catholic church, many sects do not recognize the blending of Ishtar worship with Passover.
Burnt offerings and it occured during religious times like the passover.
Yes.
The first Passover was in Egypt