Answer:
Water sample showing pink/purple color is an error.
Explanation:
Biuret is a blue color reagent that changes its color to pink/purple whenever it detects protein in a sample. Water don't contain proteins so it should not show pink/purple color instead it should maintain the blue color. Food items generally contain proteins so it show pink/purple color but it showed blue color.
Error might have caused by wrong marking of the samples, test tube marked with Water might contain a mystery food while Mystery food tube might contain water.
The smoke increases effectively increasing the planetary albedo, forcing is less however and tends to be insensitive to the solar geometry
<span>Are pollution can cause acid rain and the acid rain can hurt lots of living things. </span>
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