3.11 i'm not sure about measurements maybe like 3.11kg/cm^3
It is a Compound.
Water can't be a mixture because it is chemically bonded and cannot be separated into H2 and O by physical means.
And water cannot be an element, because it is made of atoms of different types [H and Oxygen]
Frequency = speed of light/ wavelength of photon. wavelength = speed of light/frequency = 3 x 10^8 / 2.43 x 10^8= 1.23m
You are right sugar is a mixture and salad, water and potassium are all wrong.
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