Answer:
3. The unit cost per item
Step-by-step explanation:
We are given,
The x-axis represents the number of identical items and y-axis represents the total cost in dollars.
Since, the slope of a graph is equal to the change in y-coordinates by change in the x-coordinates.
i.e. Slope is given as the change in the total cost by the change in the number of items purchased.
i.e. Slope represents the cost of an item in dollars.
Thus, it gives that the slope is the cost per item in dollars.
Hence, option 3 is correct.
