Answer: 90 mm²
Explanation:
We will use the given formula for surface area, substitute known values, and simplify by multiplying and adding.
SA = 2(wl + hl + hw)
SA = 2((2 mm)(5 mm) + (5 mm)(5 mm) + (5 mm)(2 mm))
SA = 2(10 mm² + 25 mm² + 10 mm²)
SA = 2(45 mm²)
SA = 90 mm²