Micro: Perfect and Monopolistic Competition

[domyy]

Hello guys,

There is something that I should study but is not on my book.

I am trying to find other explanations online but I can't.

So, it's pretty much to calculate quantity and price for perfect competition and monopolistic competition.

Then, consumer surplus for perfect competition and monopolistic competition.
Then, ∏ (profit) for both,
Then, deadweight loss for both.

Then, I should graph it. Take all the numbers, the information I got, and have them in one graph.

But I am lost. This is one of the examples my prof gave in class. I would like someone to give me, PLEASE, a better and easier explanation.It all starts with P = 12 - 2Q MC = 4

 

[Pyrrhus]

Here's a hint the MC is the supply function.

 

[domyy]

I know that for perfect competition, P = MC
So,
12 - 2q = 4
q = 4
p = 4

For monopolistic competition MR = MC

Now, how to find MR?

 

[domyy]

Never mind. I already know how to solve it. Thanks.