Answer
First we need the total equiv. cap.
C = 150•120/(150+120) = 67.7 nF
total charge stored Q = CV = 68v x 67.7 nF = 4533 nC or 4.533 µC
this charge is on each cap.
For C1 (left) V1 = Q/C = 4533 nC / 150nF = 30.22 volts
For C2 (right) V2 = Q/C = 4533 nC / 120nF = 37.78 volts
note that they add up to 68 volts as a check.
For C1, E1 = ½CV² = ½150nF•30.22² = 68490 nJ
or, rounding, 68 µJ
For C2, E2 = ½CV² = ½120nF•37.78² = 85640 nJ
or, rounding, 86 µJ