Question : A solid cylinder having a base of radius 7 cm and a height of 5 cm is bisected from its height to get two identical cylinders. What will be the percentage increase in the total surface area?

Option 1: 58.33 percent

Option 2: 64.56 percent

Option 3: 69.44 percent

Option 4: 52.56 percent

Question : The total surface area of a right circular cylinder with a radius of the base 7 cm and height 20 cm, is:

Option 1: 900 cm²

Option 2: 140 cm²

Option 3: 1000 cm²

Option 4: 1188 cm²

Question : If the curved surface area of a cylinder is 1386 sq cm and the height is 21 cm, what will be its radius? (Take $\pi=\frac{22}{7}$)

Option 1: 21 cm

Option 2: 5.25 cm

Option 3: 10.5 cm

Option 4: 15.75 cm

Question : 24 equal solid hemispheres are melted to form a right circular cylinder of radius 12 cm and height 24 cm. Find the radius of each solid hemisphere.

Option 1: 4 cm

Option 2: 8 cm

Option 3: 6 cm

Option 4: 3 cm

Question : A solid sphere of radius 4 cm is melted and cast into the shape of a solid cone of height 4 cm. The radius of the base of the cone is______.

Option 1: 8 cm

Option 2: 4 cm

Option 3: 6 cm

Option 4: 10 cm

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. $\mathrm{(Use ~\pi =\frac{22}{7})}$

Option 1: 15 cm

Option 2: 25.5 cm

Option 3: 17.5 cm

Option 4: 21 cm