How many of the following can be treated as 3D objects: Box, Book, Drawing sheet?
2 objects, Box and the book.. Which has the length , breadth and height ( thickness) .. A drawing sheet is a 2-d figure with only length and breadth
A 3D object has length, breadth and height.
Here box and book have length, breadth and height but the drawing sheet has only length and braedth.
Therefore, the answer is 2.