Geometry

Question Analysis:  
This question involves finding the diagonal of a rectangle, which can be solved using the Pythagorean Theorem.  
The main focus is on applying the theorem to a real-world shape (a rectangle).  

Key Concept Explanation:  
A rectangle’s diagonal forms a right triangle with its length and width as the legs. The formula is:  
 
where:  
- m (one side)  
- m (the other side)  
- is the diagonal.  

Step-by-Step Solution:  
1. Apply the Pythagorean Theorem: