Final answer:
The nurse observes that Medea's anger is growing, as shown by her increased restlessness and irritability.
Eplanation:
When the nurse observes Medea's anger, she notes that it is growing. The emotional turbulence Medea experiences is evident in the restlessness and feverish excitability seen in her behavior. Unlike her usually calm demeanor, she is becoming more agitated and irritable—signs of her mounting rage.
The nurse's observations are a testament to this escalating anger, which is intensifying as the narrative progresses.