title: how to return the requested shape using linq?
body: <p>How to create that rectangle in a multi-line string and return 
  it?<br>
  You must use '*' character to make that rectangle. The width will be the number of stars in each line, and the height will be the number of lines. </p>
  
  <blockquote>
    <p><strong>Attention:</strong>  You can only use Enumerable and Linq to generate your
    answer. Do not use 'for' loop in your answer.</p>
  </blockquote>
  
  <p>Example:  width = 10, height = 5      </p>
  
  <p>Result: </p>
  
  <pre><code>**********
  **********
  **********
  **********
  **********
  </code></pre>