Where are most of the members of opec located?

Does anyone know the answers for these

[ou.01]which of these is the most likely use of an electromagnetic wave which has wavelength shorter than microwaves but longer than visible light? o heat food safely o neat food safely o take images of bones and teeth o transmit radio and cellular phone signals o take images of bones and teeth o transmit radio and cellular phone signals o detect the location of objects which emit heat

What are economic benefits of building dams