Question : A right pyramid stands on a square base of diagonal $10\sqrt2$ cm. If the height of the pyramid is 12 cm, the area (in cm²) of its slant surface is:

Option 1: 520 cm²

Option 2: 420 cm²

Option 3: 360 cm²

Option 4: 260 cm²

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 : A right prism stands on a base 6 cm equilateral triangle and its volume is $81\sqrt3$ cm³. The height (in cm) of the prism is:

Option 1: 9

Option 2: 10

Option 3: 12

Option 4: 15

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

Question : The base of a right pyramid is an equilateral triangle of side $10\sqrt3$ cm. If the total surface area of the pyramid is $270\sqrt3$ sq. cm. its height is:

Option 1: $12\sqrt3$ cm

Option 2: $10$ cm

Option 3: $10\sqrt3$ cm

Option 4: $12$ cm