a$)$ For the rectangular section shown below the maximum allowable tensile stress in the concrete Fct $=3$ MPa $.$ Assume an cracked section and find the maximum moment the section can resist as well as the stress in the reinforcement for this moment. $(10$ marks$).$

$E_c$:$=30*GPa$

$E_s$:$=200*GPa$

$b$:$=300mm$

$h$:$=520mm$

$d$:$=460mm$

$A_s$:$=1470m{m}^2$

Do not ansssume the yield stress