Answer: -2 per day.
Step-by-step explanation:
Given: During a 2-day period, Paul and Alissa's stock price had a change of -4.
Thus, Change in stock = -4
Time period = 2 days
The average change in a subject is given by :-
[tex]\text{Average change}=\frac{\text{total change}}{\text{time period}}[/tex]
Therefore,
[tex]\text{Average change}=\frac{-4}{\text{2}}\\\Rightarrow\ \text{Average change}=-2[/tex]
Hence, The average change per day = -2 per day.
