alphabet $=\{$a$,$ b$,$ c$\}.$ A message is considered secure if it satisfies all the following conditions: a$.$ Starts and ends with the same symbol, which can be either $\text{'}$a$\text{'},\text{'}$b$\text{'},$ or $\text{'}$c$\text{'}.[10$pts$]$ b$.$ Contains no consecutive identical symbols $($no immediate repeats such as $\text{'}$aa$\text{'},\text{'}$bb$\text{'},$ or $\text{'}$cc$\text{'}).[10$pts$]$ c$.$ Has exactly two occurrences of the symbol $\text{'}$b$\text{'}.[10$pts$]$ d$.$ Does not contain the substring $\text{'}$ac$\text{'}.[10$pts$]$ Since, model verification is often costly in real$-$life, your manager asked you to validate and verify your design with a finite state machine. Design a finite state machine $($i$.$e$.,$ NFA$)$ for each of the conditions a$,$ b$,$ c$,$ and d$.$