Question 724089
The surface area of the base is the surface are of a square with a side length of 4 units.
That area is 16 square units:
{{{(4unit)(4unit)=16unit^2}}} .
The sides of the pyramid are four triangles with a base length of 4 units, and a height of 8 units.
The surface area of one such triangle (in square units) is
{{{4*8/2=16}}}
The surface area of all four sides plus the base (in square units) is
{{{4*16+16=highlight(80)}}}