What is the likely cause of the blockage in the following scenario? A plumber, cleaning out recently blocked lines, indicates that there are roots blocking the sewer system. There are no trees immediately over the sewer line and have not
been for years, there is only a small group of trees on the side of the property, several yards from the line.

Answer is in the photo. I couldn't attach it here, but uploaded it to a file hosting. link below! Good Luck!

cutt.ly/wzUiVyK

the electromagnetic spectrum includes, from longest wavelength to shortest: radio waves, microwaves, infrared, optical, ultraviolet, x-rays, and gamma-rays.

the correct answer: the index of refraction of the second medium is lower i tried this persons answer and it was wrong this person is lying