The half-life of a certain medication is 2 hours, and a patient takes a single 400-milligram dose of the medication.
After 6 hours, there will be X milligrams of medication left in the patient's body.

After 7 hours, there will be X milligrams of medication left in the patient's body. Round your answer to the nearest hundredth.

After 8 hours, there will be X milligrams of medication left in the patient's body.