The heart rate is different while dancing, studying and riding a bike because the amount of blood needed for each activity is different. Blood pumps as fast as it as needed by the cells, which is why riding a bike has fast heart rate while studying has a regular heart rate.
Answer:
Explanation:
The sum of the number of protons and neutrons in the nucleus is called the mass number of the isotope. The most common carbon atoms have six protons and six neutrons in their nuclei.