title: TypeError: no implicit conversion of Array into String
body: <p>I am receiving a error on the line <code>= select_tag :ethnicity, ['Asian', 'Black', 'Biracial', 'Indian', 'Hispanic/Latin', 'Middle Eastern', 'Native American', 'Pacific Islander', 'White', 'Other'], prompt: 'ethnicity/race'</code> that reads <code>no implicit conversion of Array into String</code></p>
  
  <p>Can someone assist?</p>
  
  <p>index.html.slim:</p>
  
  <pre><code>  = form_tag searches_path, method: :get do
            .select4
              .col.col7 style='margin-left: 10px;width:233px;'
                = select_tag :ethnicity, ['Asian', 'Black', 'Biracial', 'Indian', 'Hispanic/Latin', 'Middle Eastern', 'Native American', 'Pacific Islander', 'White', 'Other'], prompt: 'ethnicity/race'
  </code></pre>