Phsyical properties are a.) those properties that cannot be changed b.) those properties which require a chemical reaction to be observed c.) those properties which can be observed without changing the identity of the substance d.) those properties which include combustibility, flammability, and reactivity e.) all of the above

Hello!

I believe physical properties are C) Those properties which can be observed without changing the identity of the substance .

I hope it helps!

speed

ratio of distance traveled to time interval

net force

vector sum of forces on object

object

source of diverging light rays either luminous or illuminated

don't remove my answer im trying my best to answer them

explanation:

the answer is a. hope this .