a)Sectiunea diagonala, triunghi isoscel cu un unghide 60 grade, tr.echilateral
diagonala bazei 12
latura bazei 6√2
aria bazei (6√2)²=72cm²
apotema= √(12²-*(3√2)²)=3√14
arie laterala=(4*6√2*3√14):2=72√7cm²
arie totala 72(1+√7)cm²
b)Ab/Al =x/100
1/√7=x/100
x=(100:√7)%≈37,8%
c) h piramida=12√3/2=6√3
Vol piram = (1/3)*72*6√3=144√3cm³