Geometry

Question Analysis:  
This question involves applying the Pythagorean Theorem in a rectangle, where the diagonal forms the hypotenuse of a right triangle.  
The main focus is on finding the diagonal when the two sides are given.  

Key Concept Explanation:  
For a rectangle with length and width , the diagonal is found using:    

Step-by-Step Solution:  
1. Identify given values:  
  - Length:  
  - Width:  
  - Diagonal: (unknown)  
2. Apply the Pythagorean Theorem: