Ok too start off with the key is;
Project_Teams = {A,B,C}
Workforce = {1,2,3,4,5}
the question is;
Decide if the statement Project_Teams $\displaystyle \in$P(Workforce) is true or false.
I'd love to help you, but this question is incoherent.
Project and Workforce are supposed to be sets, I gather? And you are using $\displaystyle \in$ to mean "belongs to the set"? What is $\displaystyle P$?
If you are asking whether it makes sense to write: {A, B, C} $\displaystyle \in$ {1, 2, 3, 4, 5} without giving any indication of what these set elements mean, then I would have to say no.
If you are asking something else, then you need to explain it better.
The elements of Project_Teams are set (presumably with elements in Workforce) while Workforce is a set whose elements are workers. If this is the case no, Project_Teams is not an element of Workforce (which is what you are asking) since Project_Teams is not a worker.
CB