$3$ solid cubes whose edges are $6, 8$ and $10 \, cm$ respectively,are melted and formed into a single cube. If there is no loss of metal in the process,find the edge of the new cube (in $cm$).

$A$ cube of edge $3\, cm$ of iron weighs $12\, gm$. What is the weight of a similar cube of iron whose edge is $12\, cm$? (in $gm$)

$A$ tank $3\, m$ long,$2\, m$ wide and $1.5\, m$ deep is dug in a field $22\, m$ long and $14\, m$ wide. If the earth dug out is evenly spread out over the field,the level of the field will rise by nearly (in $cm$)

$A$ solid sphere and a solid hemisphere have the same total surface area. The ratio of their volumes is

$A$ rectangular water tank is $80 \, m \times 40 \, m$. Water flows into it through a pipe with an opening area of $40 \, cm^2$ at a speed of $10 \, km/h$. By how much will the water level in the tank rise in half an hour (in $cm$)?

If the length,breadth and height of a rectangular parallelopiped are in the ratio $6:5:4$ and if the total surface area is $33,300\, m^{2}$,then the length,breadth and height of the parallelopiped (in $m$) respectively are: