Find the lateral surface area of the cuboid which measures $50 \, cm \times 40 \, cm \times 30 \, cm$. (in $cm^2$)

The diameter of a solid hemisphere is $7 \, cm$. Find its curved surface area and total surface area (in $cm^2$).

Two cubes each of $8 \, cm$ edge are joined end to end. Find the total surface area of the cuboid so formed (in $cm^{2}$).

The surface area of a cube whose edge is $a$ is: (in $a^{2}$)

$A$ cylindrical tube open at both ends is made of an iron sheet which is $2 \, cm$ thick. If the outer diameter is $16 \, cm$ and its length is $100 \, cm$, find how many cubic centimeters of iron have been used in making the tube? (in $cm^3$)

How many cubes of $1 \,cm$ edge can be cut from a wooden cuboid measuring $5 \,cm \times 4 \,cm \times 3 \,cm$? Find the ratio of the total surface area of the cuboid to the total surface area of all the cubes.