Plants need carbon in the form of?
carbon dioxide
fossil fuels
cellular respiration
photosynthesis

The terrestrial planets are characterized by having a a.) silicate core b.) iron-rich silicate core c.) iron-rich metallic core d.) none of these

As an asteroid comes close to earth, it's name will change to? apex

Which description shows competition in an environment? an organism that feeds on some food an organism that finds a place to sleep three organisms of the same species living in an area three organisms battling over limited resources