16) which of these is a physical property? a) boiling point b) flamability c) reactivity d) toxicity

A) boiling point

Explanation:

Chemical property is defined as the property of a substance which is observed during a reaction where the chemical composition identity of the substance gets changed.

Physical property is defined as the property which can be measured and whose value describes the state of physical system. For Example: State, density etc.

Boiling point is a physical property as it involves change of state.

Flammability is a chemical property as there is formation of new substances.

Reactivity is a chemical property as there is formation of new substances.

Toxicity  is a chemical property as there is formation of new substances.

there is none because earth is stationary and flat.