Describe the economic advantage of using sodium-vapor lights and a disadvantage of the color it produces

Sodium-vapor lights are using sodium to produce light. The great economic advantage of using sodium-vapor is because of its reasonable cost. It has longer life span and highly efficient. However, it's great disadvantage is the color it produces. The color of the light the sodium-vapor produces is yellow which is not recommendable to use in outdoor like streets.

Maybe haha

The type of rock she find is a sediment rock