**Category:** Optics  
**Subtype:** Refraction and Dispersion  
**Problem Description:** This problem involves a transparent plastic sheet with parallel sides and a thickness of 10 cm. A narrow beam of white light is incident on the top surface of the sheet at an angle of \(i=60^{\circ}\). The refractive indices for red and violet light are given as \(\mathrm{n}_{\mathrm{d}}=1.42\) and \(\mathrm{n}_{\mathrm{t}}=1.44\), respectively. The task is to find the width of the spectrum that emerges from the plastic sheet.  

**Objective:** Calculate the width of the spectrum of light (the difference in the angles of refraction for red and violet light) as it exits the plastic sheet.