Being underweight can contribute to a very frail and weakened immune system. It can make one feel tired mentally. And can also affect the bones by making them very brittle and frail sometimes.
Answer:
50 to 100 times each minute.
Explanation:
During activity or excitement, your body needs more oxygen-rich blood; the heart rate rises to well over 100 beats per minute. Medications and some medical conditions may affect how fast your heart-rate is at rest and with exercise
