I need help solving the question listed below urgently. Please provide a detailed answer. Thank you

Let $H=\{\begin{array}{c}{r}^n{0}^h{f}^m\end{array}$ where $n,m,h0,$ and $\{$:$nh\}$

a$.$ Construct a CFG that generates the strings of points$)$

b$.$ Does the string rooof belong to H$?$ Justify your answer

using a sentential form derivation approach $(10$ points$)$

c$.$ Simplify the grammar you have constructed using

the approach studied in lectures. $(20$ points$)$

d$.$ Does the string roofff belong to $H?$ Justify your answer

using a derivation tree approach from the simplified grammar $(10$

points$)$