2. Perimeter = (15+10) × 2+5× 2 = 60cm area =15×10-5× 5 =125cm 2.
3. The shaded area = 36× 24-(18+36-4 )×18 ÷ 2 = 414cm2.
4. (5+7) × 7 ÷ 2+5 × 5 ÷ 2-(5+7) × 7 ÷ 2 =12.5 cm2.
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