Final answer:
Nathan wonders if Ira has lost her powers because the newborn baby is a girl, which had different societal implications at the time the story is set.
Step-by-step explanation:
After Ira's baby is born, Nathan wonders if Ira has lost her powers because the baby is a girl. In the historical context of the story, having a male heir was often considered important. Ira's deception to raise her daughter as a boy, to ensure that the father's lineage and promises are kept, touches on gender expectations and inheritance customs of the time.
Nathan's wonder reflects societal beliefs about gender roles and the importance of male offspring. In the play or text that the student is referring to, Nathan wonders if Ira has lost her powers after the baby is born.
The question asks for the reason behind Nathan's wonder but does not provide options for us to choose from. However, based on the context and information provided, we can infer that Nathan might wonder if Ira has lost her powers because the baby cries constantly, is malnourished, or is a girl.