The correct answer is “ me ayudas?”
Yo nado en la piscina
Nosotros nadamos en la piscina
Yo trabajo en la escuela
Nosotros trabajamos en la escuela
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: