( kg / m ) 12 ( kg ) 8 0.395 4.74 10 0.617 7.404 12 0.888 10.656 13 1.04 12.48 14 1.21 14.52 15 1.39 16.68 16 1.58 18.96 18 2 24 19 2.23 26.76 20 2.47 29.64 22 2.98 35.76 25 3.85 46.2 28 4.83 57.96 32 6.31 75.72 36 7.99 95.88