Question

the ability of a joint and a muscle group to move through a full range of motion is referred to as a muscular endurance

Answer 1

Nope, it's Flexibility

Answer 2

And in reference to muscle endurance it’s the ability of a muscle or group of muscles to sustain repetitive contractions against a resistance for an extended amount of time. :)

Answer 3

http://www.livestrong.com/muscular-endurance/

an interesting site....

Answer 4

Could either be mobility or flexibility. I recommend these sites. they are rich with articles which are no-nonsense. Most of what you've probably heard your whole life is misinformation; I've gone through this myself.
www.ericcressey.com
robertsontrainingsystems.com
www.precisionnutrition.com
Here is your one-stop shop to anything related to exercise, nutrition, fitness, etc. It will keep you very busy. But ALWAYS learn. but most importantly..apply what you learn. You will be amazed at what the proper implementation of correct nutrition, exercise, and recovery does for you.