Question

a student wanted to test the hypothesis that adding antifreeze to water lowers the freezing point of water. the student found that pure water froze at 0° c, while the water/antifreeze mixture froze at -20° c. in order to confirm the results, the student should repeat the experiment using a container of a different size. a different amount of antifreeze. a different amount of water. exactly the same set - up as the first experiment.

Explanation:

To confirm the hypothesis that adding antifreeze lowers water's freezing point, the experiment should be repeated with the same setup (same amounts, container, etc.) to ensure validity. Changing container size, water amount, or antifreeze amount would introduce variables, while repeating with the same setup (the teal option: "exactly the same set - up as the first experiment") controls variables and allows reliable confirmation.

Answer:

The correct option is the teal - colored one with the text "exactly the same set - up as the first experiment".