Explanation:

LED TVs are slimmer but also more expensive ,plasma screen TV on the other hand ,have better picture quality , but are less energy efficient and usually available in larger sizes.
    While an LED screen uses light emitting diode as backlights for the screen , plasma screens light themselves using gas cells that emit ultraviolet light.

project loon is a research and development project developed by X(FORMERLY  GOOGLE  X) with the mission of providing internet access to rural and remote areas .the project uses high altitude balloons  placed in stratosphere at an altitude of about 18 km create an aerial wireless network with upto 4G-LTE speeds.