If you mean a healthy relastionship
1. Honesty
2. Communication
3. Commitment
Hope this helps
The blood vessels dilate to increase the "blood traffic" through the lungs to carry more oxygen to the muscle. The lungs work harder (faster respiratory rate) to increase the rate of oxygen/carbon dioxide exchange in the lungs.
Answer:
I believe it depends, but it can range from two weeks to three months. It all depends on how fast your personal eyebrow growth is.