Step-by-step explanation:
the surface consists of 6 squares. but for the lateral surface area we ignore top and bottom (you can imagine we only calculate the walls of a room). that leaves 4 squares.
each square has the same side length of 1.8 cm.
so, the area of one square is 1.8² = 3.24 cm²
and the total lateral surface area of the 4 squares is
3.24×4 = 12.96 cm²
