Asteroids are relatively small to large chunks of celestial body that have dark surface. other asteroids are thought to be rocky and to have a core made of A. Iron or cobalt
B. Cobalt or Nickel
C. Nickel or Zinc
D. Iron or Nickel

out of these options:

ability to burn paper

pure sodium reacting violently with water

the boiling point of water

helium does not tend to react with anything

i would say this is a physical property:

helium does not tend to react with anything

why? :

i said helium does not tend to react with anything because well, it reacts to ! but ability to burn paper, pure sodium reacting violently with water, & the boiling point of water are chemical or

physical properties: the properties of a substance that can be observed without changing the chemical makeup of the substance

chemical properties: properties of a substance relating to the chemical nature and reactivity of the substance

it is reliable if two scientists recorded it