no 31,32 ada yang tau

31) a = 21 m
b = 11 m
t = 12 m
L = 1/2 × (a + b) × t
= 1/2 × (21 + 11) × 12
= 1/2 × 32 × 12
= 192 m^2

32) QR = 20 m
PS = 12 m
PQ = 6 m
SR = 10 m
L = 1/2 × (QR + PS) × PQ
= 1/2 × (20 + 12) × 6
= 1/2 × 32 × 6
= 96 m^2