Kindly go through all the following questions

Central West Virginia Energy Company, a West Virginia coal sales company, along with Massy Coal Company, a Virginia corporation, filed a lawsuit in federal district court against Mountain State Carbon and its member companies, one of which, Severstal Wheeling, was located in Wheeling, West Virginia. The plaintiffs alleged that the defendants, all of which were in the steel business, refused to accept ship- ments of coal in breach of their supply agreement with Central Energy. The defendants filed a motion to dismiss for lack of diversity, claiming that both Severstal and Central Energy had their principal places of business in West Virginia. The district court dismissed the complaint for lack of diversity, citing that Severstal's self-described day-to-day operations, such as "purchasing, sales, transportation, engineer- ing, human resources, and accounting/financial functions," are all handled in Wheeling and noting Severstal's "visibility in and involvement with the Wheeling community." The plaintiffs appealed, argu- ing that the court misinterpreted Hertz and that the district court failed to consider the importance of the2. Cox-Ingersoll-Ross (CIR) Model. Let (2, F, P) be a probability space and let { W, : 1 2 0} be a standard Wiener process. Suppose X, follows the CIR model with SDE dX , = k (0 - X, ) di + o \\X,dW, Xo>0 where k, 0 and o are constants. By applying Ito's formula to Z, = extX, and Z? = e2xx2 and taking integrals show that for t