6. A bucket with a volume of 12 liters was filled to the top with gravel, and then water was added until it started to overflow over the edge of the bucket. Find the density of the material of the gravel particles if an additional 3 liters of water fit into the bucket, and the weight of the bucket became 28 kg. Assume the weight of the empty bucket is 1 kg. Recall that a liter of water weighs 1 kg.
a) $267 \mathrm{kr} / \mathrm{M} 3$

б) $2,67 \mathrm{kr} / \mathrm{m} 3$

в) $200 \mathrm{Kr} / \mathrm{m} 3$

г) $2,00 \mathrm{kr} / \mathrm{m} 3$

д) $225 \mathrm{kr} / \mathrm{m} 3$
6. $267 \mathrm{kr} / \mathrm{m} 3$.

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