In the provided layout, a $6-$inch slab is supported by beams positioned along gridlines $1,2,$ and $3.$ The applied live load on the slab is $100$ lb$/$ft$2.$ The beams have dimensions of $15$ inches by $18$ inches, and the entire structure is upheld by nine columns of equal strength, each measuring $20$ inches by $20$ inches. Each column can withstand a maximum load of $33150$ pounds. Given that the distance between gridlines A$-$B and B$-$C is assumed to be equal, what is the maximum spacing permissible between column lines A and B $($ designated as x in the layout$)$ to ensure that the load does not surpass the columns' capacity?It is assumed that the density of concrete is $145$ lb$/$ft$3.$ Give your answer in a whole number.Figure $1$: Building Top View$1$