Final answer:
An average person's reflexes and alertness start to decline at a BAC of 0.02-0.03, and the legal limit of intoxication is a BAC of 0.08. Alcohol metabolism rates vary, but on average the liver processes alcohol at 3.3 mmol/L per hour.
Step-by-step explanation:
The blood alcohol concentration (BAC) at which an average person's reflexes and alertness begin to decline is 0.02-0.03. This level signifies the initial effects of alcohol intoxication, which often include slight euphoria and a decrease in visual functions and overall alertness. As BAC levels increase, the effects on coordination, concentration, and the ability to track moving objects become more pronounced. The legal limit for intoxication is typically a BAC of 0.08. The rate at which alcohol is metabolized varies among individuals, but the liver breaks it down at an approximate rate of 3.3 mmol/L (15 mg/dL) per hour for an average person.