A Beam with an Overhang Is Loaded by a Uniform $I_{z}=3.36 \times 10^{6} \mathrm{~mm}^{4}$

A beam with an overhang is loaded by a uniform load of 3 kN/m over its entire length. Moment of inertia $I_{z}=3.36 \times 10^{6} \mathrm{~mm}^{4}$ and
Distances to top and bottom of the beam cross section are 20 mm and
66)4 mm, respectively. It is known that reactions at A and B are 4.5 kN
And 13.5 kN, respectively. The maximum bending stress in the beam is
Approximately: (A) $36 \mathrm{MPa}$
(B) $67 \mathrm{MPa}$
(C) $102 \mathrm{MPa}$
(D) $119 \mathrm{MPa}$