Free help with homework

Why join Brainly?

  • ask questions about your assignment
  • get answers with explanations
  • find similar questions



Leonardo da Vinci (1452–1519) is generally credited with inventing the helicopter, but the first practical design was developed only in the 1930s by Russian-born Igor Sikorsky (1889–1972).

0 0 0
The Brain
  • The Brain
  • Helper
Not sure about the answer?
Learn more with Brainly!
Having trouble with your homework?
Get free help!
  • 80% of questions are answered in under 10 minutes
  • Answers come with explanations, so that you can learn
  • Answer quality is ensured by our experts