Two separation columns in sequence are used to separate the components of a feed consisting of 25% benzene (B), 50% toluene (T), and remaining xylene (X). The analysis of the overhead stream from the first column yjelds 90%B,5%T, and remaining X. The second column is designed to recover 85% of the foluene in the original feed in its overhead stream at a composition of 0.946. The bottoms at the second column are intended to contain 85% of xylene in the original feed at a oomposition of 0.776 . Compute the total mass fow rate of compounds at overhead at the first column. A. 17.9kah B. 27.69kgh c. 53.49kgh D. 23.2kgh