MN||AC||A'C"||PQ
MN=AC/2=A'C'/2=QP
MNPQ patrulater cu 2 laturi opuse paralele si congr., MNPQ paralelogram
Perim= 2(MN+MQ)
MN= AC/2=12√2/2=6√2
AM⊥(AA'D) pt ca ABCDA'B'C'D" prisma dreapta
⇒AM⊥AQ⇒QM²=QA²+AM²
QA²=AA'²+A'Q²=(6√2)²+6²=108
QM²=108+6²=108+36=144⇒QM=12
Perim =2(6√2+12)=12(2+√2)cm, cerinta