Final answer:
The metabolic half-life for retinol-binding protein is approximately 60 to 90 minutes.
Step-by-step explanation:
The metabolic half-life for retinol-binding protein is the time it takes for half of the concentration of the protein to be degraded. In the case of retinol-binding protein, its half-life is approximately 60 to 90 minutes (Source: hormone example)