'Density' is defined as (mass) / (volume). You need enough information to be able to measure or calculate the mass and the volume of the object.
Answer:
Nails rusting over time as they are exposed to oxygen
Explanation:
New substance with new property is formed
It have also changed the chemical property of the substance
It is difficult to reverse the change etc...
Answer:
B. Hold each type of fabric over a candle flame and time how long it takes for the fabric to start to burn.
Explanation:
Answer:
The slope of the graph is what you need. That tells you the speed not the velocity. In order to find the velocity you would also need to know the direction of the motion.
