Question

suppose antonio runs a small business that manufactures shirts. assume that the market for shirts is a perfectly competitive market, and the market price is $25 per shirt. the following graph shows antonios total cost curve. use the blue points (circle symbol) to plot total revenue and the green points (triangle symbol) to plot profit for the first seven shirts that antonio produces, including zero shirts.

Explanation:

Step1: Recall total - revenue formula

The formula for total revenue ($TR$) in a perfectly - competitive market is $TR = P\times Q$, where $P$ is the price per unit and $Q$ is the quantity produced. Given $P = 25$ dollars per shirt.

Step2: Calculate total revenue for different quantities

When $Q = 0$, $TR_0=25\times0 = 0$; when $Q = 1$, $TR_1=25\times1 = 25$; when $Q = 2$, $TR_2=25\times2 = 50$; when $Q = 3$, $TR_3=25\times3 = 75$; when $Q = 4$, $TR_4=25\times4 = 100$; when $Q = 5$, $TR_5=25\times5 = 125$; when $Q = 6$, $TR_6=25\times6 = 150$; when $Q = 7$, $TR_7=25\times7 = 175$.

Step3: Recall profit formula

The formula for profit ($\pi$) is $\pi=TR - TC$, where $TC$ is the total cost. We need to read the total - cost values from the given graph for each quantity $Q$.
Let's assume the total - cost values from the graph for $Q = 0,1,\cdots,7$ are $TC_0,TC_1,\cdots,TC_7$ respectively.
For $Q = 0$: $\pi_0=TR_0 - TC_0=0 - TC_0$ (read $TC_0$ from the graph, assume $TC_0 = 25$, so $\pi_0=- 25$)
For $Q = 1$: $\pi_1=TR_1 - TC_1=25 - TC_1$ (read $TC_1$ from the graph)
For $Q = 2$: $\pi_2=TR_2 - TC_2=50 - TC_2$
For $Q = 3$: $\pi_3=TR_3 - TC_3=75 - TC_3$
For $Q = 4$: $\pi_4=TR_4 - TC_4=100 - TC_4$
For $Q = 5$: $\pi_5=TR_5 - TC_5=125 - TC_5$
For $Q = 6$: $\pi_6=TR_6 - TC_6=150 - TC_6$
For $Q = 7$: $\pi_7=TR_7 - TC_7=175 - TC_7$

To plot:

• For total revenue, the points are $(0,0),(1,25),(2,50),(3,75),(4,100),(5,125),(6,150),(7,175)$ (blue points).
• For profit, calculate the profit values for each $Q$ as above and plot the points (green points).

Since we don't have the exact numerical values of the total - cost for each quantity from the graph to give a single numerical answer for profit, the process to find the points for plotting is as above. If we assume the total - cost values at $Q = 0,1,\cdots,7$ are $25,40,55,70,90,115,150$ respectively:
For $Q = 0$: $\pi_0=0 - 25=-25$
For $Q = 1$: $\pi_1=25 - 40=-15$
For $Q = 2$: $\pi_2=50 - 55=-5$
For $Q = 3$: $\pi_3=75 - 70 = 5$
For $Q = 4$: $\pi_4=100 - 90 = 10$
For $Q = 5$: $\pi_5=125 - 115 = 10$
For $Q = 6$: $\pi_6=150 - 150 = 0$
For $Q = 7$: $\pi_7=175 - 190=-15$

The points for total revenue are $(0,0),(1,25),(2,50),(3,75),(4,100),(5,125),(6,150),(7,175)$
The points for profit (assuming the above - calculated values) are $(0, - 25),(1,-15),(2,-5),(3,5),(4,10),(5,10),(6,0),(7,-15)$

Answer:

To plot total revenue: blue points at $(0,0),(1,25),(2,50),(3,75),(4,100),(5,125),(6,150),(7,175)$
To plot profit: green points at (values calculated as above, e.g., if using assumed values: $(0, - 25),(1,-15),(2,-5),(3,5),(4,10),(5,10),(6,0),(7,-15)$)