If each edge of a cube is increased by $50 \%$,the percentage increase in surface area is (in $\%$)

Find the curved surface area (in $cm^{2}$) of a hemisphere of diameter $28\, cm$.

$A$ semicircular sheet of metal of diameter $28 \, cm$ is bent into an open conical cup. The capacity of the cup (taking $\pi = \frac{22}{7}$) is (in $cm^3$):

$A$ 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 $gm$)

If the radius of a cylinder is doubled and the height is halved,then what would be the ratio between the new curved surface area and the previous curved surface area of the cylinder?

$A$ rectangular tank is $30\,m$ long and $20\,m$ broad. Water is being flown into it through a square pipe of side $5\,cm$. What is the speed of water if the level of water in the tank rises by $1\,m$ in $8\,hours$? (in $km/h$)