Question No$.3$

The part floor plan for the internal panel of an office building is shown in the Figure. The floor is precast concrete slabs $125mm$ thick supported on steel beams.

The following loading data may be used:

$125mm$ concrete slab $=3\mathrm{.}0k\frac{N}{m}2,$

Screed finishes $=1\mathrm{.}0k\frac{N}{m}.$

Partition $=1\mathrm{.}0k\frac{N}{m}L,$

Imposed load $=3\mathrm{.}0k\frac{N}{m}2.$

Design the floor beams, assuming that the self weight of main beams and secondary beams may be taken as $0\mathrm{.}5$ and $1\mathrm{.}0k\frac{N}{m}$ run, respectively.

I need a step$-$by$-$step explanation of how to calculated and final answer