Using the grammar in Example $3\mathrm{.}4,$ show a parse tree and a leftmost derivation for each of the following statements:

a$.A=(A+B)**C$

b$.A=B+C+A$

c$.A=A***(B+C)$

d$.A=B**(C**(A+B))$

Example $3\mathrm{.}4$

An Unambiguous Grammar for Expressions