Okay. So Nina's fourth bounce is 6 feet high. The following bounces will be 2/3 as high as the previous. That is also similar to exponential decay. 6 is 2 away from 4. For this, we will raise 2/3 to the 2nd power. We can basically just multiply it together. 2/3 * 2/3 is 4/9. Now, we multiply that fraction by 6. 6 is 6/1 as a fraction. 6/1 * 4/9 is 24/9 or 2 2/3 in simplest form. There. Nina's sixth bounce will be 2 2/3 feet high.