The two columns in Figure $6\mathrm{.}19$ are to be supported on a combined footing. The vertical dead loads on

Columns A and B are $500$ and $1400$ kN$,$ respectively. Using the ASD method for ultimate limit state

design, determine the required dimension B$2$ so the resultant of the column loads acts through the centroid

of the footing and express your answer as a multiple of $100$ mm$.$