How much pure alcohol is contained in each of the following: a 12 oz beer, 4 oz wine, 1 ¼ oz 80 proof alcohol or 1 oz 100 proof alcohol?

The amount of pure alcohol contained in each of the following is as follows:
A 12 oz beer: On average, a regular 12 oz beer contains approximately 0.5 oz (1/2 oz) of pure alcohol.
4 oz wine: A standard 4 oz serving of wine typically contains about 0.5 oz (1/2 oz) of pure alcohol.
1 ¼ oz 80 proof alcohol: 80 proof alcohol is 40% alcohol by volume (ABV). Therefore, 1 ¼ oz (1.25 oz) of 80 proof alcohol contains approximately 0.5 oz (1/2 oz) of pure alcohol.
1 oz 100 proof alcohol: 100 proof alcohol is 50% alcohol by volume (ABV). Thus, 1 oz of 100 proof alcohol contains approximately 0.5 oz (1/2 oz) of pure alcohol.
Therefore, in each case, the amount of pure alcohol is approximately 0.5 oz (1/2 oz).