Question : The radius of the base of a solid right circular cone is 8 cm and its height is 15 cm. The total surface area of the cone is:

Option 1: 200$\pi$

Option 2: 120$\pi$

Option 3: 136$\pi$

Option 4: 128$\pi$

Question : The height and the radius of the base of a right circular cone are in the ratio of 12 : 5. If its volume is 314 cm³, then what is the slant height of the cone? (Use $\pi$ = 3.14)

Option 1: 12 cm

Option 2: 11 cm

Option 3: 13 cm

Option 4: 14 cm

Question : The curved surface area of a right circular cone is $156 \pi$ and the radius of its base is 12 cm. What is the volume of the cone, in cm³?

Option 1: $192 \pi$

Option 2: $210 \pi$

Option 3: $240 \pi$

Option 4: $180\pi$

Question : A cylinder of height 8 cm and radius 6 cm is melted and converted into three cones of the same radius and height of the cylinder. Determine the total curved surface area of cones.

Option 1: $180 \pi\operatorname{cm^2}$

Option 2: $60 \pi\operatorname{cm^2}$

Option 3: $144 \pi\operatorname{cm^2}$

Option 4: $120 \pi\operatorname{cm^2}$

Question : Three metallic spheres of radii 10 cm, 8 cm, and 6 cm, respectively are melted to form a single solid cone of radius 12 cm. Find the curved surface area of the cone, correct to two places of decimal. (Take $\pi=3.14$)

Option 1: $1664.50 \text{ cm}^2$

Option 2: $1669.86 \text{ cm}^2$

Option 3: $1876.79 \text{ cm}^2$

Option 4: $1864.41 \text{ cm}^2$