PLEASE HELP (will give brainliest): A sample of food is dehydrated, which kills all of the bacteria. However, in a few days, bacteria-free water is added to the food in a bacteria-free environment. Nevertheless, microscopic investigations indicate that bacteria are in the food. How did the bacteria get there?

Because the cells in the dehydrated fruit become re-hydrated with the water which then gives the cells in both the water and the fruit the tools that it needs to "come alive" if you will. And the cells become active in the fruit and use the water to grow bacteria.

Explanation:

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.