The diameter and length of a roller is 120 cm and 84 cm respectively. To level the ground, 200 rotations of the roller are required. Find the expenditure to level the ground at the rate of ~ 10 per sq. m.

If the radius and height of a road roller are 0.5 m and 1.4 m respectively, then find the area of field pressed in 100 rotations.

The diameter and thickness of a hollow metallic sphere are 12 cm and 0.01 m respectively. The density of the metal is 8.88 gm per cm^3 . Find the outer surface area and mass of the sphere.

Find the area of the sector whose arc length and radius are 10 cm and 5 cm respectively.

Two sound waves having wavelengths of 87 cm and 88.5 cm respectively , when superimposed, produce 10 beats per second . Find the velocity of sound .

An oil funnel of tin sheet consists of a cylindrical portion 10 cm long attached to a frustum of cone. The diameters of the top and bottom of the frustum are 18 cm and 8 cm respecti8vely. If the slant height of the frustum of the cone is 13 cm, find the area of the tin required to make the funnel from the given information in the figure (pi=3.14)

A cuboidal box open at the top has length, breadth and height 20 cm, 16cm and 10 cm respectively . Find its volume.

Volume of a cuboid is 520 cm^(3) . The length and breadth of the cuboid are 10 cm and 6.5 cm respectively . Find its height.