Identify the type of question. Is it a literature research question, observation only question, demonstration question, or investigation question?

How would you determine the PH of vinegar using cabbage juice as an indicator? (investigation)

Do germaniting seeds produce heat?
(Investigation)

Does Kentucky Bluegrass or Bermuda help best prevent soil erosion? (Demonstration)

Can you blow up a ballon with yeast cells and a bottle? (Demonstration)

Can you separate plant pigments using chromatography? (Investigation)