question 3

require 'nokogiri'

html = Nokogiri::HTML(<<-HTML)
  <div class="attr">
    <ul>
      <li>Lorem</li>
      <li>Ipsum</li>
      <li>Dolor</li>
    </ul>
  </div>
HTML

p result = html.css('div.attr ul li').map(&:text)
# => ["Lorem", "Ipsum", "Dolor"]