Actually girls grow more than boys because girls develope faster and mature faster.
She needs to put the fingertip on ice to preserve it increasing the chances of medical staff being able to reattach it. Then seek medical help as soon as possible to stop the bleeding and prevent any infection in the wound and to have the fingertip reattached.
It called the Pectoral muscles
C. Not all exercise takes max effort. You can walk as exercise but it’s not putting forth as much as a run or sprint.