A. Although the bell curve for most babies to be done with reflux (spitting up) is around six months, some still have it until the first year of life (and a few beyond that).
If she is spitting up effortlessly, it is not uncomfortable, and she is gaining weight, it is a matter of cleaning up and being patient for it to resolve on its own. Solid foods help since they are heavier and stay down. Thicker formula using pre-thickened products, like Enfamil AR or Similac SR, or adding a thickening agent like Simply Thick to expressed breast milk may also help keep things down for the same reason--you are using gravity to your advantage. It helps to keep your baby upright after feedings for at least 20 minutes also--so the food can leave the stomach and enter the small intestine (so it won't come back up).
If the spitting up is entirely new for your baby at 9 months of age, if she is uncomfortable, avoiding meals, or not gaining weight, then you need to check in with her doctor.