The answer would be D) Geiger counter.
Answer:
"Heat of combustion"
Explanation:
A physical property is characteristic of a substance that can be observed or measured without changing its chemical composition, such as color, molecular weight, and volume. A chemical property can only be observed or measured by changing the chemical composition of the substance, such as reactivity, flammability and oxidation states.
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Na, Ba, Cs and Ni are metals.