Odpowiedź:
1. heart
2. because it has to send more blood to other muscles
3. heart sends more blood to brain when we exercise. it makes us sleep better, feel happy and we can learn more quickly.
4. they are getting weaker
5. we have 206 bones in our human bodies
6. there are 52 bones in our feet
Wyjaśnienie:
liczę na naj :)
