Answer:
A. Chemical change
Explanation:
When vinegar and baking soda are first mixed together, hydrogen ions in the vinegar react with the sodium and bicarbonate ions in the baking soda. The result of this initial reaction is two new chemicals: carbonic acid and sodium acetate.
You would expect to find the center of gravity in a ruler in the middle because if you were to cut a ruler in half, depending on the center of gravity, you would have two equal pieces, which mean there is equal weight, meaning the middle is the center of gravity
