Question : The radius and slant height of a cone are in the ratio 5 : 7. If its curved surface area is 1347.5 cm², find its radius. $\mathrm{(Use ~\pi =\frac{22}{7})}$

Question : The total surface area of a cylinder whose radius is 6 cm and height is 8 cm is: (Use $\pi=\frac{22}{7}$)

Question : If the radius of a sphere is increased by 2 cm, then its surface area increases by 352 cm². The radius of the sphere initially was: (use $\pi =\frac{22}{7}$)

Question : If the slant height and radius of a right circular cone are 28 cm and 21 cm, respectively, then the total surface area of the right circular cone (in cm²) is: (Take $\pi=\frac{22}{7}$)

Question : The sum of the radius of the base and the height of a cylinder is 42 m. If the total surface area of the cylinder is 6336 m², find the curved surface area of the cylinder correct to two places of decimals (use $\pi=\frac{22}{7}$).