CDS || Weekly_Revision_Quiz_2020

If

where x, y, z are natural numbers, then what is z equal to?

Let V be the volume of an inverted cone with vertex at origin and the axis of the cone is long positive y-axis. The cone is filled with water up to half of its height. The volume of water is:

A river 2.5 m deep and 45 m wide is flowing at the speed of 3.6 km/hour. The amount of water that runs into the sea per minute is:

From an external point P tangents PA and PB are drawn to the circle as shown in the above figure. CD is the tangent to the circle at E. If AP = 16 cm, then the perimeter of the triangle PCD is equal to

In a mixture of milk and water of volume 30 litre, the ratio of milk and water is 7 : 3. The quantity of water to be added to the mixture to make the ratio of milk and water 1 : 2 is:

The minimum value of cos²x + cos²y - cos²z:

A person standing 1 m in front of a plane mirror approaches the mirror by 40 cm. The new distance between the person and his image in the plane mirror is

Which one among the following metals is prominently used in mobile phone batteries?

An object is raised to a height of 3 m from the ground. It is then allowed to fall on to a table 1 m high from ground level. In this context, which one among the following statements is correct?

Who among the following proposed that atom is indivisible?