A hollow ball.....
A sphere and a cylinder can roll straight.
cylinder
Rectangular Hollow Section Pipe means that shape of cross-section of RHS pipe is not round or circle but rectangular or oblong.
A common answer to the riddle "What is round but does not roll?" is a coin. Coins are typically circular in shape but usually remain stationary when placed flat on a surface. Other possible answers could include a plate or a button, as they also have a round shape but do not roll.
A spherical shape like a ball.
A hollow cylinder.
No. The numbat is not like an armadillo. It does not roll into any spherical shape when threatened. Its only defence is to hide in hollow logs and crevices in trees or rocks.
Sleepy Hollow
a hollow pear
A hollow cylinder.
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.
A solid ball rolls faster than a hollow ball.
Cube
cuboid
Fossil
a 44mm sphere that is hollow