For the building frame showm, assuming the column$-$beam connections are rigid, find the following: $($weights shown at each floor does not include the weight of the beams and the columns. Add the weight of the beams and the columns to the weight at each floor$)$

Modal natural periods of vibration $($ & $T)$

First and second normalized mode shapes

Base shear for both modes

Story forces and shears for both modes

Columns' $I=2700$ in ${?}^4$

Beams are W$24$x$68$

Columns W$24$x$94$

$S_a=0\mathrm{.}8g$

$S_d=3$ inches