Questions for Parashah #50

Continuing in Parashah Va'era, here are several questions for our coming weekly study. The reading is #50 in the triennial cycle, a schedule of which can be found at Torah Resource.

Exodus 7:19-8:16
Joel 3:9-21
Romans 9:17-18

Link to Torah Resource Commentary

The questions are below. Please feel free to leave your thoughts, questions, and responses in the comments section.

1. Based on Exodus 7:25, "and seven days passed," and other textual clues, the Sages formulated that the period of each plague was one month total: approximately three weeks warning of the plague, and one week or seven days of the duration of the plague, after which the plague would end by default. In several cases in the administration of the ten plagues, Pharaoh pleaded for an earlier end to the plague, a plea that was granted by the Almighty through the agency of Moses and Aaron. This teaches us several things: 1) that Hashem does not send a punishment or judgment without a significant period of warning. Question/challenge: list several verses stating this principle and narratives in the Torah and prophets that emphasize this aspect of Hashem's mercy 2) The week, or seven day, duration of the plagues has eschatological overtones, especially since in the Sages' formulation the period of the week can be "cut short" by divine decree. Question/challenge: expound on the eschatological overtones and cite a reference(s) of the period of judgment being cut short.
2. This portion covers the first three plagues: blood, frogs, and lice. As the narrative progresses, Pharaoh is alternately adamant in his opposition to letting the people go and in his desire for mercy in the midst of the plagues, signs, and wonders. Is there a method to Pharaoh's madness, his swings between arrogance and entreaty? The Sages explain that whenever Pharaoh felt his own life at stake, he pleaded for mercy, but in all other cases the plague was irritating but not life-threatening so he hardened (literally, "made strong") his heart. Does this interpretive tool help explain Pharoah's actions? In what sense? In what ways is this interpretation a stretch?

I hope to add a question or two before Shabbat from the Haftarah and Apostolic portions. In the meantime, may the Holy One, blessed be He, enliven our minds to comprehend His Word in sincerity and truth.