Respuesta :

1 gallon = 4 quarts

1 quart = 32 ounces, 1 quart = 32 ounces*1 glass/8 ounces = 4 glasses

1 quart = 4 glasses

1 gallon = 4 quarts = 16 glasses

If Sam drinks 4 glasses per day. and he has 16 glasses, then 16/4 = 4 days

Answer is 4 days.