Which of these are 3 dimensional objects?
Coffee Mug
Birthday Hat
book
Coffee mug - The shape is cylindrical.
Birthday Hat - The shape is conical.
Book - The shape is cuboid.
These are all three dimensional objects as they have length, breadth as well as height.
But, page from your not book is a two dimensional object. It has length and breadth but its thickness is very less as compared to its other dimensions which is why it is not cinsidered as a three dimensional object.