Depends.
well if you are mixing by volume it is 1:2:4 and it can be 1 of anything a bucket or pail or whatever as long as you use the same measure for all 3...5 gallon buckets or shovelsfull are the norm...so...
In Ethiopia it costs around 15USD due to the soaring inflation(2nd to Zimbabwe) and the monopoly of the market by the government.
I have no Idea maybe you can look on google and they might tell you or maybe ask your science teacher.
It is usually 50kg.
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