Using the PhET simulator, build 3 atoms of your choice. 1. After each build, take a screenshot and add it to the Seesaw activity on page 1 2. Choose 1 of your atoms. Click on the + sign beside Net Charge and Mass Number to see it. Select Stable/Unstable at the bottom right-hand corner so that all three options are checked. 3. Add a few electrons. Now, take some away. What happens? Answer the question on page 2 4. Add some neutrons. Now, take some away. What happens? Answer the question on page 2. 3. Answer the last question on page 2 and click on when done.