a$)$ Provide the context$-$free grammar for the following language $L=\{a^n{b}^k{c}^{n+k}|n,k0\}.$

b$)$ Provide the equivalent CFG for the regular expression: $1^1{0}^{+}{1}^{+}{1}^{+}$

c$)$ Given the DFA below, provide the equivalent context$-$free grammar.