Layers

there are four layers,
      in the atmosphere
first is the troposphere
      heaviest layer
      lowest layer!
second is the stratosphere
    here is the ozone layer
        aircraft fly here
third is the ionosphere
radio and t.v. signals are beamed here
signals come back to earth from here
fourth is the exosphere
    thinnest air
     is here
    uppermost layer
  space starts from here

EVERY CHILD READS IN FIFTH CLASS
THE LAYERS OF ATMOSPHERE