Final answer:
To measure the weight of a can of soda, the most appropriate units would be ounces or pounds, as gallons are for liquid capacity and tons are for very large items.
Step-by-step explanation:
To measure the weight of a can of soda, you would use ounces or pounds. Considering the options provided and the size of the object, a can of soda typically weighs about 12 ounces or 0.75 pounds. Ounces are the smallest common unit of weight in the customary system and are appropriate for very light items such as a can of soda. Pounds are also a common unit for measuring weight and can be used when precision to the ounce is not necessary. Gallons are a unit of liquid capacity and not weight, while tons are used for very large items such as vehicles, so they are not suitable for measuring something as small as a can of soda.