Scientists think that algae first evolved approximately 2.7 billion years ago, and soon after this oxygen began to exist in the atmosphere. Photosynthesis by primitive plants and algae released oxygen, which gradually built up in the atmosphere.
Explanation:
Answer: A, D, A, B
Explanation: La = feminine singular Las = feminine plural El = masculine singular Los = masculine plural
hope this helps :)
It means "six by three equals to"
Escuchamos
Creerán
Escuche