a. had a low specific heat?
If water had a low specific heat, then life on Earth would be almost impossible due to our inability to handle fluctuations in temperature. The ability to handle these changes in real life is due to the fact that our bodies are made up of about 75% water which has a high specific heat and therefore regulates out body temperatures during fluctuations. If water were to have a low specific heat, then our bodies would not be able to maintain a safe temperature range supporting of life.
b. had a different range of melting and boiling points?
If water had a different range of melting and boiling points, then these temperatures would not coincide with our body temperatures and may be a solid or a gas in our bodies- neither of which serve the proper functions in our system of water. In solid and gas forms, water doesn’t have the properties of a polar molecule and therefore won’t work as a solvent, a regulator, or an environment for chemical reactions.
c. was not a good solvent?
If water was not a good solvent, then it would not allow for distribution/diffusion of vital substances in and out of our cells and also wouldn’t allow any necesary reactions which depend on an aqueous solution. also, many parts of our cells would become dysfunctional such as our cell membranes. These are made up of a phospholipid bi layer that relies on the polarity of water (polarity makes water a good solvent) to stay intact.