30 metallic cylinders of the same size are melted and cast in the form of cones having the same radius and height as those of the cylinders.

Consider the following statements

1.A maximum of 90 cones can be obtained

2.The curved surface of the cylinder can be flattened in the shape of a rectangle but the curved surface of the cone when flattened has the shape of a triangle

Which of the above statements are correct?

Water is filled in a container in such a manner that its volume doubles every 5 minutes.If it takes 30 minutes for the container to be full,in how much time will it be one-fourth full?

From the solid gold in the form of a cube of side length 1cm,spherical gold balls each having surface area (π)^(1/3) cm² are to be made.Assuming that there is no loss to the material in the process of making the balls,the maximum number of balls made will be

The circumference of a circle is 100cm.The side of a square inscribed inside the circle is

A large water tank has the shape of a cube.If 128m³ of water is pumped out,the water level goes down by 2m.Then the maximum capacity of the tank is

Consider the following statements

1.If the height of a cylinder is doubled,the area of the curved surface area is doubled

2.If the radius of a hemispherical radius is doubled,its total surface area is four-fold

Which of the above statements is correct?