Answer:
S.A. = 234 mm²
Step-by-step explanation:
The formula of a surface area of a rectangular prism:
[tex]S.A.=2(lw+lh+wh)[/tex]
l - length
w - width
h - height
We have l = 15 mm, w = 3 mm, h = 4 mm. Substitute:
[tex]S.A.=2(15\cdot3+15\cdot4+3\cdot4)=2(45+60+12)=2(117)=234[/tex]
