$(12$ points$)$ The system X has users Anna, Matt, and David. Anna cannot access David$$s files, and neither Anna nor David can access Matt$$s files. Matt can access Anna$$s files and David$$s files. David can access Anna$$s files. $($Each user can access their own files.$)$

The system Y has users Holly, Sarah, and Heidi. Sarah cannot access either Holly$$s or Heidi$$s files. Holly can access Sarah$$s files and Heidi$$s files. Heidi can access Holly$$s files and Sarah$$s files. $($Each user can access their own files.$)$

The composition policy says that Matt and Holly can access one another$$s files, and Anna can access Sarah$$s files.

Apply the Principles of Autonomy and Security to determine who can read whose files in the composition of X and Y$.$ Assume that if something neither allowed nor forbidden by principles, then allow it$.$