Fred is the lead hardware engineer on your project. In the past, Fred's work was good to excellent. Fred was someone you could count on and delegate to, a responsible and responsive team member. Now Fred misses work, some of his deliverables are late, and his work is not up to the quality of previous assignments. In meetings, he becomes hostile and argumentative. When Sam, a junior member of the team asks Fred for help in a meeting you are chairing, Fred accuses him of being lazy and unable to do his job. Sam tells Fred that the whole team knows that Fred is coasting on past achievements and should be fired! As the project manager, how would you handle this situation?