Peter was holding a Human Physiology textbook that weighs about 4lbs with his non- writing arm for one minute. His elbow remained exactly at a 45° isometric position. He did not complain of any muscle fatigue or muscle weakness. a) i. Is the number of activated motor units stay the same while he was holding the book for two minutes? (0.5 pt) ii. Why? (0.5 pt) Increasing the period Peter is holding the texting will only cause the motor units to fire more frequently to keep the muscles from relaxing. b) i. Are the same motor units activated while he was holding the book for two minutes? (0.5 pt) ii. Why? (0.5 pt)