Not a kid asking for homework need volume help?

Use a plastic bag not a rigid container.

A 10 lb turkey would have a displacement of about 1.3 gallons

If you use a plastic bag 1 gallon of brine would do just fine for the a plastic bag, Just make sure that your plastic bag can hold over 5 gallons ( need room to form a nice seal).

If you decide to use the 28lbs plastic container which holds about 3.2 gallons then you will need about 2 gallons of brine.

Your turkey probably has close to the density of water, and water is roughly 8lbs / gallon, so your turkey will have a volume of a little more than a gallon, if you add 2 gallons of brine you'll have a little more than three gallons total. If your container holds say three and a half or more gallons, it should be fine, if it holds three (or less) you'll have to use less water or it will overflow.

Since I don't know the density of your detergent I don't know how big your 28lb container is, but you could find out by filling it with a measured amount of water.

However, I would be a bit concerned about residual oder from the detergent, perhaps lining the container with a plastic bag would be a good idea.

it depends on the specific volume of the brine and the turkey, as we proceed to the computation 1 gallon of water is equivalent to 3.78541Li so if we add the turkey + the brine it will surely be able to hold it in a plastic container.. if you use brine the specific gravity approximately 1.03 -1.07, well for turkey i don't know its specific gravity...try to research for it

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