During the carboniferous period, plants and animals grew very large due to high concentration of a. oxygen in the atmosphere. b. nitrogen in the atmosphere. c. carbon dioxide in the oceans. d. argon in the oceans .

Option A, oxygen in the atmosphere

Explanation:

The highest level of oxygen reached during this phase of the geological cycle of earth. The oxygen level in  Carboniferous  period accounted for 35%  as compared to 21% of oxygen in the atmosphere in present time.

Due to high oxygen content, the giant and wide varieties of terrestrial animal and plant species evolved. For example – size of insects and carwlies increased, plant became extremely giant, increase in number of tree ferns etc.

the answer to your question is slate

the answer is admiramos

the rule for verbs is whoever you are referring to (in this case 'nosotros'), you need to change the ending of the word.

nosotros - amos

yo - o

tu - as

el, ella, usted - a

ellos, ellas, ustedes - an

(examples: nosotros bailamos (instead of bailar) or yo hablo (instead of habla)