octagon
6 faces with 4 right angles on each face, so 6 x 4 = 24 right angles
A rectangular prism has six faces; each face has four right angles. There are 24 right angles in all.
A shape with five sides would be a pentagon, but a shape can not have 5 right angles. Squares and Rectangles are both shapes with 4 sides and 4 right angles. They are the only shape with the same amount of right angles as there is sides.
A regular 5 sided pentagon is one such example of a shape having no right angles
A tetrahedron.
Any open shape with four right angles, including the crossing axes.
A cube has 6 faces, each having 4 right angles, for a total of 24 angles.
A cuboid has twenty four right angles. A cuboid is a shape with six faces that are either squares or rectangles. Each face has four right angles.
octagon
The solid is a cuboid, or "right rectangular prism" in which all angles are right angles. It is a box shape, or regular hexahedron.
A 3-dimensional shape with three pairs of rectangular faces opposite one another; meeting at right angles.
If the question is about a plane shape with exactly 3 right angles it could be an irregular polygon of 5 or more sides. If the shape can have more than 3 right angles then a square or rectangle are also possible. Finally, in 3 or more dimensions, a polyhedron with any number of faces can have 3 or more right angles.
Square-based pyramid.
there are 24 right angles in all faces of a cube
A sphere!
6 faces with 4 right angles on each face, so 6 x 4 = 24 right angles