I would say developed technologies which somehow were lost
like the stone age: the stone hammer, who used that afterwards in the roman empire era and stuff?
Answer: The density of the object will be 
Explanation:
Density is defined as the mass contained per unit volume.
Given : Mass of object = 19.6 grams
Volume of object= 
Putting in the values we get:
Thus density of the object will be
due to there reactive rate?
Answer:
True
Explanation:
Yes I agree object can be in motion and in not motion at the same time for example there are two men travelling on the bus one person is A another person is B. the person be B rest so by seeing person be the person A also sits but the person see who saw the person be B move along with person C so the the person be B is in rest for person Abut is motion for a person C.
