Question : The height and the total surface area of a right circular cylinder are 4 cm and 8$\pi$ sq cm, respectively. The radius of the base of the cylinder is:

Option 1: $\left ( 2\sqrt{2}-2 \right )\ \text{cm}$

Option 2: $\left ( 2-\sqrt{2}\right )\ \text{cm}$

Option 3: $2\ \text{cm}$

Option 4: $\sqrt{2}\ \text{cm}$

Question : The volume of a solid right circular cylinder of height 8 cm is $392 \pi$ cm³. Its curved surface area (in cm²) is:

Option 1: $161 \pi$

Option 2: $96 \pi$

Option 3: $210 \pi$

Option 4: $112 \pi$

Question : The curved surface area of a right circular cone of a base radius of 21 cm is 594 sq. cm. What is the slant height of the cone?

Option 1: 15 cm

Option 2: 11 cm

Option 3: 9 cm

Option 4: 6 cm

Question : The curved surface area of a cylinder is five times the area of its base. Find the ratio of the radius and height of the cylinder.

Option 1: 2 : 3

Option 2: 3 : 5

Option 3: 2 : 5

Option 4: 3 : 4

Question : A right circular cylinder has a height of 18 cm and a radius of 7 cm. The cylinder is cut into three equal parts (by two cuts parallel to the base). What is the percentage increase in total surface area?

Option 1: $62\%$

Option 2: $56\%$

Option 3: $48\%$

Option 4: $52\%$