Two masses `m_(1)` and `m_(2)` are attached to a string which passes over a frictionless smooth pulley. When `m_(1)=10kg,m_(2)=6kg`, the acceleration of masses is
A. `(f-(m_(2)-m_(1))g)/(m_(1)+m_(2))`
B. `((m_(1)+m_(2))g-f)/(m_(1)-m_(2))`
C. `((m_(2)-m_(1))g-f)/(m_(1)+m_(2))`
D. `(m_(2)g-f)/(m_(1)+m_(2))`
