<li>
          <b>P04_FUN</b> evaluates the integrand for problem 4.
        </li>
        <li>
          <b>P04_TITLE</b> returns the title for problem 4.
        </li>
        <li>
          <b>P05_EXACT</b> returns the exact integral for problem 5.
        </li>
        <li>
          <b>P05_FUN</b> evaluates the integrand for problem 5.
        </li>
        <li>
          <b>P05_TITLE</b> returns the title for problem 5.
        </li>
        <li>
          <b>P06_EXACT</b> returns the exact integral f