Answer:
508sq. cm
Step-by-step explanation:
surface area of a prism = 2(lw + wh + lh)
For the larger prism
Surface area = 2(2*10 + 2 * 12 * 10*12)
Surface area = 2(20+24+120)
Surface area = 2(164)
Surface area = 328sq.cm
For the smaller prism
Surface area = 2(3*6 + 3 * 8 * 6*8)
Surface area = 2(18+24+48)
Surface area = 2(90)
Surface area = 180 sq.cm
Surface area of the figure = 328 + 180
Surface area of the figure = 508sq. cm