Question about corona

Which part of a feedback mechanism is able to monitor the conditions outside of cells and usually uses nerve cells to relay this information to an intergrating center

For each of the following compounds, write the formula then predict whether it would be a strong, weak, or non-electrolyte when placed in di water. for the ionic compounds only, put (s) or (aq) after the forrmula formula strong, weak or non electrolyte? a calcium hydroxide b. silver carbonate c. lead(ii) sulfate d. phosphorus trifluoride e. sodium phosphide f barium sulfate g. strontium acetate h. zinc nitrate

How could a student test the effect of removing heat from a gas that is stored in a sealed container? what must occur in order for matter to change states?