A chemical property describes how a substance undergoes a chemical reaction. Cadmium reacting with nitric acid forms new substances (cadmium nitrate), producing a blue solution. The other options are physical properties.

For addition, the number of decimal places must match the term with the fewest decimal places.

• $0.12$ has 2 decimal places
• $0.003$ has 3 decimal places
  The sum is:

Rounded to 2 decimal places:

Extensive properties depend on the amount of matter. Length changes when the amount of material changes, while color and melting/freezing points are intensive properties that do not depend on sample size.

Accuracy means hitting close to the true value (center). Precision means repeated hits are close together. Since all darts land close to the center and close to each other, the thrower is both accurate and precise.