How many barrels of oil are used per day in the us?

18.19 mil

Explanation:

In 2020, the United States consumed an average of about 18.19 million barrels of petroleum per day, or a total of about 6.66 billion barrels of petroleum.

ecological efficiency: % of usable energy transferred as

biomass from one trophic level to the next typical is 10% efficient (90% of

energy is lost),is diagramed as the pyramid of energy flow. then osprey eagle

are tertiary consumer and the shrimp are primary consumer, so to balance

mass of shrimp (1/0.1) / 0.1 = 100 kg 

the answer is cell division : )