Please please please answer i have to turn this in today and I really don’t understand it

Its B. 7.7 %

Explanation:

By putting the value of beef that is 13 in the above formula and multiply by 100 you will get 7.7 %. 7.7 percent is the conversion efficiency for beef. Conversion efficiency refers to the amount of energy which is produced after the input of some material or substances. In beef, more energy is produced as compared to other materials when input of 1 kilogram is consumed.

the national environmental policy act (nepa) is a united states environmental law that promotes the enhancement of the environment and established the president's council on environmental quality (ceq). the law was enacted on january 1, 1970. to date, more than 100 nations around the world have enacted national environmental policies modeled after nepa.

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