Odpowiedź:
a)
a = 120mm = 12cm
b = 40mm = 4cm
h = 3cm
P = 1/2 (a+b) × h
P = 1/2 (12 + 4) × 3= 24
b)
a = 1dm = 10cm
b = 70mm = 7cm
h = 40mm = 4cm
P = 1/2 (10+7) ×4= 34
