Area of parallelogram = a*h=10*3=30 ,there are 2 such parallelograms in the prism
2 faces are rectangles with sides 12 and 6 ,
Area of this face is 12*6=72, there are 2 such faces
2 faces are rectangles with sides 12 and 10
Area of this face is 12*10=120, there are 2 such faces
2*30+2*72+2*120 = 444 cm²