Which of the following colours is dispersed the least through a prism?

How many rectangular surfaces are there in a prism?

The refraction of light by a prism is shown in the following figure. Then $\angle D$ is:

Explain the refraction of light with the help of a Glass Prism.

A student traces the path of a ray of light through a glass prism as shown in the diagram, but leaves it incomplete and unlabelled. Redraw and complete the diagram. Also, label on it $\angle i, \angle e, \angle r$ and $\angle D$.

What is dispersion of light? Will there be dispersion of white light within a glass slab after refraction when white light is incident on the glass slab at an angle of ${45}^{\circ }$?

What causes the dispersion of white light? 

Differentiate between a glass slab and a glass prism.