Please answering the following question, thank you!

Problem 2. To understand formation and stability of cartels, we consider a simple market structure with 4 firms produce a homogeneous good in a Cournot competition environment. Each firm with the same constant marginal cost c = 2. Firms face an inverse demand given by P(Q) = 100 - Q. 1. If 3 firms choose to form a cartel, is this cartel stable