A tetrahedron (4 faces) and an icosahedron (20).
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There is no such thing as a 3d triangle. A 3d shape which has only equilateral triangular faces can be a tetrahedron which has 4 faces or an icosahedron which has 20.
In geometry, a deltahedron (plural deltahedra) is a polyhedron whose faces are all equilateral triangles. The name is taken from the Greek upper case delta (Δ), which has the shape of an equilateral triangle.
Only one; a triangle is a 2D shape, not a 3D shape. Usually only 3D (or more) shapes are considered to have 'faces'.
cylinder
An icosahedron.