a$)AG+4$ OMRF building has plan dimension as shown

Numerical Data :

Size of column $-300mm450mm$

Size of beam $-250mm300mm$

Depth of slab $-125$ mm

Floor height $-3\mathrm{.}3$ m

Infill wall $-250$ mm thick including plaster in exterior and $125$ mm in interior

Imposed load $-3k\frac{N}{m^2}$ in floor level and roof level is $1\mathrm{.}5k\frac{N}{m^2}.$

The soil below the foundation is medium and the building is located in Kolkata. Determine the seismic forces and shears at different floor levels by using IS $1893($Part $1)$:$2002.$