The process of converting nitrogen gas in the air into nitrates in the soil is known as
a
nitrification
b nitrogen fixation
assimilation
d denitrification

In what way are cities microclimates?

Which type of transport is responsible for oxygen entering into blood cells? a. vesicle b.passive c. facilitated d.active b.passive

The earths core is made up mainly of what 2 substances? 2. like an egg, earth has a core, a layer surrounding the core, and a thin, hard outer layer. which layers of the earth match the layers of an egg?