It is often stated that the four Gospel accounts of Jesus’ resurrection contradict each other and cannot be harmonized. ?What

[Note that for the sake of thoroughness, this question asks you to consider one chapter from Luke's Gospel that is part of next week's assignment]

It is often stated that the four Gospel accounts of Jesus' resurrection contradict each other and cannot be harmonized.  What is your assessment of this claim?  Are there parts of the story that do not fit together?  What about common elements in all four of the Gospels that complement each other?  

Using the four accounts of visitors to Jesus' tomb on "the first day of the week" after his crucifixion (Matthew 28, Mark 16, Luke 24 and John 20), write an extended essay that conveys both what these stories have in common and how they differ regarding events at the tomb and immediately afterward (limiting your discussion to the chapters listed here). Briefly reflect upon why these differences may exist and whether they invalidate the claim that Jesus did in fact rise from the dead on the third day.  Be honest in your reflections.