tolong dibantu yaa,,

((a)) P = F / A = 500 N / 28 m = 17,8 N/m²
A = 2(pl+pt+lt) = 2(50×10 + 50×15 + 10×15) = 2 (500+750+150) = 2×1400 = 2800 cm = 28 m 
((b)) P = F / A = 700 N / 23m = 30,4 N/m²
A = 2(pl+pt+lt) = 2(40×10 + 40×15 + 10×15) = 2 (400+600+150) = 2×1150= 2300cm = 23m
((c)) P = F / A = 1000N / 88m = 11,3N/m²
A = 2(pl+pt+lt) = 2(60×20 + 60×40 + 20×40) = 2 (1200+2400+800) = 2×4400 = 8800cm = 88m
((d)) P = F / A = 1000N /33m = 30,3 N/m²
A = 2(pl+pt+lt) = 2 (40×10 + 40×25 + 10×25) = 2 (400+1000+250) = 2×1650 =3300 cm = 33m

tekanan paling besar pada balok B
maaf yang kuat arus lupa caranya