The solutions among the given mixtures are sea water, air, and soda water.
Explanation: A solution is a homogeneous mixture where the components are evenly distributed throughout. Sea water, air, and soda water all have a uniform composition with their components evenly mixed.
Sea water: Salt dissolved in water
Air: A mixture of various gases like nitrogen, oxygen, and carbon dioxide
Soda water: Carbon dioxide dissolved in water
Why the other options are not solutions:
Soil: Soil is a heterogeneous mixture with different components like sand, clay, and organic matter not evenly distributed.
Coal: Coal is also a heterogeneous mixture with varying composition throughout.