Suppose the marginal product of labor for unskilled labor is given by MPN = 200 – 0.5N. The supply of unskilled labor is given by 100 + 4w. The government imposes a minimum wage of 40. How much unemployment will this create among unskilled labor?
I don't know i should be answering your question since it's directed to a specific person, But i will proceed.
MPN curve given is the demand function of labor by firm or whatever. MPN is basically the real wage. The supply curve of labor is somethn like
and you equate it with MPN.