<p>
  <b>Mars</b> is one of the most Earth-like planets. <b>Mars</b> day is almost the same as an Earth day, only
  <strong>37 minutes</strong> longer.
</p>

<p class="irrelevant">
  <b class="important">NASA</b>'s Jet <del>Momentum</del> Propulsion Laboratory is designing mission concepts to survive
  the <b>Venus</b> extreme temperatures and atmospheric pressure.
</p>

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