No it does not make your breasts hang.
Probably not, since running has to do with your legs, but it might, because it makes you healthier. Try doing other exercises, too.
Only small breasts stay up by themselves. Breast mainly contains of fat so the weight will make them hang. There is a muscle behind the breast so that can not hold it up. If men get more breast tissue they also hang.
Breast augmentation is for enlarging a breast size, but there is a surgery for breast reduction. Each surgery does a different shaping to the breast. One makes it larger and the other makes it smaller.
She is running a marathon for Breast Cancer Awareness.
No the weight, pregnancy and age makes them sag.
hormons
Genetics and hormones.
The gerund is "running"
if you run daily, Yes, or more
To Support the breast. You don't want them to bounce around or begin to hang. Padded bras are worn to provide an illusion of bigger breast or to hide the protrusion of the nipple.
No it does not.
chicken.