Having accurate Specific date can give scientist what they need for more reliabliltiy.
Answer:
you need only one independent variable because if not, you wont know what factors have changed your experiment.
Explanation:
The soulustion. turn cloudy due to the precipitation of Sulphur.
Im a bit torn here, lets look at the definitions of physical and chemical changes:
physical change changes only the phase/state of a substance, but not what the substance is
chemical change is a chemical reaction where a new substance is formed and energy is given off or absorbed.
(it just started raining and it smells really nice out my window)
clearly, this cannot be just a physical reaction. i think i would be inclined to pick B. but C. could have merit as an answer too. sorry for the ambiguity x
