It is a rectangular shape. If you were to roll out the whole roll it would be rectangular! And weird question! I like it! ;)
A cylinder.
Cube
A sphere and a cylinder can roll straight.
A cylinder
A pyramid will not roll and you cannot stack objects on top.
A heptagon based prism has 8 vertices and it can roll.
A cylinder
a bagel
it is a cylinder
A hollow ball.....
Rolled cookies are easier to roll and shape when the dough is thoroughly chilled - at least for several hours.