An iron pillar consists of a cylindrical portion 2.8 m high and 20 cm in diameter and a cone 42 cm high is surmounting it. Find the weight of the pillar, given that 
of iron weighs 7.5 g
Given,
Height of cylinder R = 2.8m = 280cm
Radius = 
Height of cone = 42cm
Volume of pillar = volume of cone + volume of cylinder
= 
Given that,
Weight of 1 cm3 iron = 7.5gm
Weight of the pillar = 92400 × 75
Weight of the pillar = 693000g
= 693kg
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