As a venture capital manager, you are interested in investing a new founded company, StocProc. StocProc is a pharmaceutical company that focuses on research and development $($RD$)$ of a new drug. There are significant risks associated with the RD of this new drug. The status of this new drug can be categorized into five different states: S$1,$ S$2,$ S$3,$ D$1,$ D$2,$ and F$.$

The status of this new drug can be modeled by a Markov Chain. Let Xt