Answer:
B: Unit conversions express an amount in a different unit.
Explanation:
You need a control so you have something to compare the experimental group on-- If you don't have a control group, how will you know what's changed?
The answer is helium 0.09 kg/m³.
The wave will move faster in the gas that is having lowest density.
As comparison to other gases-hydrogen, oxygen and radon; helium has the lowest density that is 0.09 kg/m³.
So, waves will move fastest in helium gas as it is having lowest density.
So the answer is helium gas that is waves will move fastest in helium gas.
The metric prefix kilo means 1,000.
Example: A kilometer is equal to 1,000 meters.
Answer:
matter
Explanation:
any thing that has mass and volume is matter. basically everything expect light and energy.