$(20$ pts$.)$ The interior$-$column$-$free $12$ node model below has ${10}^{\text{'}}{10}^{\text{'}}$ ceiling bays $({20}^{\text{'}}{30}^{\text{'}}$ total dimension$),$ and is ${10}^{\text{'}}$ high. The short vertical central members $($extending under the roof$)$ are $2^{\text{'}}$ long. If there is a wind load of $300$ #$/$ft pushing across the leftmost $20\text{'}$ edge of the roof, and a gravity load of $400\frac{\text{\#}}{f}{t}^2,$ what is the total force in columns A and B$,($indicating tension or compression$)?$