When the island of Krakatoa was destroyed by a volcanic eruption, the sound waves could be detected worldwide. How long would it take for such a wave to travel around the earth and come back to Krakatoa? (seconds)

• Assumptions used and why.
• Equations needed to determine variables necessary for developing the solution and why the equations were necessary.
• Description of how you developed the values for variables.
• Description of your level of confidence in the variable values.
• Overall level of confidence in the solution and why.