Final answer:
The answer to the question is d) Leucine, as an example of an essential amino acid and a) 0.8, as the RDA for protein in g/kg of healthy body weight.
Step-by-step explanation:
An example of an essential amino acid is d) Leucine. Essential amino acids are those that our body can't synthesize on its own, and thus, we must obtain them through our diet. Leucine can't be produced by the body, making it one of the nine essential amino acids.
The Recommended Dietary Allowance (RDA) for protein is a) 0.8 g/kg of healthy body weight. This means, for a healthy individual, for every kilogram of body weight, they should consume 0.8 grams of protein.
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