A pyramid of slant length 6cm stands on a square base 4cm by 4cm.find

a.)the total surface area
b.)the volume of pyramid to 1dp

the area is the square base, plus four triangles, each with base=4, height=6

V = 1/3 Bh
Draw a side view, and it should be clear that
h^2 = 6^2 - (4/2)^2