Hej!
[tex]P_p=\frac{1}{2}\cdot3\cdot4=\frac{1}{2}\cdot12=6 \ [ \ j^2 \ ]\\\\P_b=4\cdot6+3\cdot6+5\cdot6=24+18+30=72 \ [ \ j^2 \ ]\\\\P_c=2\cdot P_p+P_b=2\cdot6+72=12+72=\boxed{84 \ [ \ j^2 \ ]}[/tex]
Pozdrawiam! - Julka
