The source of heart for a (an) close system is electricity.
You're fishing for "polarization".
Answer:
Concave Lens Uses. Telescope and Binoculars Spectacles Lasers Cameras FlashlightsPeepholes. ...
Used in telescope and binoculars. ...
Concave lens used in glasses. ...
Uses of concave lens in lasers. ...
Use of concave lens in cameras. ...
Used in flashlights. ...
Concave lens used in peepholes.
All you need to do is find what location you need and look it up and see if you get the right answer bruh