Which characteristics describe the troposphere? check all that apply. is the innermost later, contains the ozone layer, has the highest air pressure, spans 12-50 km above earth, is a good place for planes to fly

The correct answers are:

- is the innermost layer;

The troposphere is the first layer of the Earth's atmosphere, thus it is the innermost one of all. This is the layer which enables life on our planet, and its composition is just the right one that life on Earth can thrive.

- has the highest air pressure;

Because this layer has the biggest density of all layers, which practically means that it has the most molecules per area, so it is the richest with gasses, this layer has the highest air pressure. The more gasses there are in a layer, the heavier it is, thus it has bigger air pressure.

if the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.