Three capacitors A, B, and C are connected in a circuit as shown in figure. What is the charge in μC on the capacitor B?

Capacitors B and C are in parallel, then A is in series.Ceq=2×(3+4)2+(3+4)=149μFQ=CeqV=149(7−6)=149μCQ will be divided between B and C. So charge on B isq=3×(14/9)3+4=23μC