Questions with the keyword 'earth'

• How did you get the idea to build an Earthquake alarm? by Sarah007 to Andrea Comments: (No comments so far )
• How Hard was it to built a earthquake alarm? And was it helpful? by Jessica109 to Andrea Comments: (So far, one comment )
• How long did it take you to build the earthquake alarm? by ava_07 to Andrea Comments: (No comments so far )