Question

the blood alcohol content (bac) is the amount of alcohol in a persons blood expressed as a(n)
level
percentage
decimal
amount

Explanation:

Blood Alcohol Content (BAC) is defined as the concentration of alcohol in the blood, typically expressed as a percentage of alcohol per volume of blood (e.g., 0.08% BAC means 0.08 grams of alcohol per 100 milliliters of blood). The term "percentage" directly describes this standard unit of measurement.

Answer:

Percentage