Va'eira 5779
The names of Hashem represent the different ways He interacts with the world. At the beginning of Va'era a transition takes place in how God interacts with the world, from א-ל שד-י to שם הויה.
The Netziv: The four expressions of גאולה correspond to the four stages of redemption which are indicated by nuances in the descriptions of the makkot.
Showing respect to gentile kings.
The plague of צפרדע: What were they? What was the nature of the plague - was it a deadly plague? Why does Pharaoh ask Moshe for the plague to cease the following day?