Please explain each parameter passing$/$returning method below. When to use it$?$ Code a function prototype example.Pass$-$by$-$const$-$lvalue$-$referenceReturn$-$by$-$autoA$\mathrm{.}5-15$ ptsstring cs $="$CSC$340"$;string& csRef $=$ cs;string$*$ const csPtr $=$ &csRef;Please use csPtr to code a pointer which points to cs$.$Change the value of cs through this new pointer.Please code an lvalue reference to reference csPtrPlease code an rvalue reference to reference $*$csRefList at least $3$ ways to change the value of cs$.$