Plasmas can interact strongly with electromagnetic radiation: this is why plasmas might plausibly be used to modify an object's radar signature.
Plasmas can have a wide range of values in both temperature and density; plasma temperatures range from close to absolute zero and to well beyond 109 kelvins (for comparison, tungsten melts at 3700 kelvins), and plasma may contain less than one particle per cubic metre, or be denser than lead.