tolong di jawab ya .........................

Luas permukaan
= 6s^2 +  (s[tex] \sqrt{2} [/tex] x t) + 2(sxt)
= 6 x 50^2 cm^2 + (50[tex] \sqrt{2} [/tex] x 40) + 2(50x40) cm^2
=  15.000 cm^2 + 2.000[tex] \sqrt{2} [/tex] cm^2 + 4.000 cm^2
= 19.000 cm^2 + 2.000[tex] \sqrt{2} [/tex] cm^2
= 2000(9,5 + [tex] \sqrt{2} [/tex] ) cm^2