27) B

Mass of container = 800g = 0.8kg
Mass of container full of water = 15.6kg
Mass of water alone = 15.6-0.8 = 14.8kg
Volume of cylinder = πr²h

If the diameter doubles, so does the radius. The question says the height also doubles.
New radius = 2r, New height = 2h
New formula = π(2r)²(2h)= π4r²2h = 8(πr²h)
Hence, the volume increases by 8 times. Therefore, weight increases by 8 times too. Volume of water = 14.8kg x 8 = 118.4 kg
Since the height and diameter double, the dimensions of the sheet also double. 
Let us assume the original sheet had dimensions of 2mx2m. The area would be 4m². The new dimensions would be 4mx4m and the area would be 16m. Therefore, area of the sheet increases by 4 times, meaning that the weight of the sheet also increases by 4. 
Weight of new sheet = 0.8kg x 4= 3.2kg
Total weight of new container full of water = 118.4 kg + 3.2 kg = 121.6 kg

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