How about a hemisphere ?
A 3D shape with one base and three faces can only have triangular faces.
CONE
Sometimes. Any face can be defined as a base of a prism; but pyramids may have one face that is a base and not a triangle.
A pyramid.
A circle is not a 3D figure because it only has two dimensions. A sphere is a 3D "circle".
A 3D figure shows length, width and depth. While a 2D figure only shows length and width.
It means the base in a 3D figure. For example, if it was a pyramid. the bottom part would be the base and you get the area of that base
To find the base of a figure, you first need to identify the shape of the figure. The base of a figure is typically the bottom or lower side that forms the foundation or support for the rest of the shape. For example, in a triangle, the base is usually the side on which the triangle stands. In a rectangular prism, the base is one of the two parallel and congruent rectangular faces.
In 2D, the only figure would be some type of dodecagone. In 3D however, there are many possibilities. One of them is the decagonal bipyramid
polyhedron
A pyramid (3D)! Some examples: - triangular base pyramid - square base pyramid - rectangular base pyramid - cone
A triangular base pyramid would fit the description.