A closed conical tank has a base diameter of 2 m and is 5 m tall. When standing in upright position, the water in the tank is 3 m deep. How deep will the water stand in the tank when in inverted position?
Three circles of different diameter are tangent externally. The triangle formed by the line joining their centers has sides 16 cm, 20 cm, and 24 cm, respectively. Find the area of the smallest circle in square cm.
A sphere of radius 18 inches is cut by two parallel planes that are 16 inches apart. Find the volume on the sphere included between these cutting planes if the radius of one of the circles cut is 15 inches.
A certain lotto game consists of 30 different balls numbered 1 to 30. If five balls are drawn at random without replacement, how many possible winning combinations can be made?