What is the importance of light?

Which one of the following has the highest wavelength?

What do you understand by monochromatic light and polychromatic light?

How fast would a rocket have to go relative to an observer for its length to be corrected to $99\%$ of its length at rest? $\left(\mathrm{c}=3\times {10}^8{\mathrm{ms}}^{-1}\right)$

Name the portion of the electromagnetic spectrum in between ultraviolet and infrared regions.

The following graph depicts the inverse of magnification versus the distance between the object and lens data for a setup. The focal length of the lens used in the setup is

Distance between the object and the lens $\left(\mathrm{m}\right)$