Answer:
16km/h
Explanation:
Vt=20km/h ---train speed
Vd=4km/h
Donas speed relative to ground is:
Vrd=Vt-Vd
Donas is moving in opposite direction of train .
Vrd=20km/h-4km/h
Vrd=16km/h
I think your answer is volume
30grams
Explanation:
If a reaction starts with 30grams then the reaction should end with 30grams.
This in conformity with the law of conservation of mass.
- The law states that "in an isolated system, mass is neither created nor destroyed during chemical transformation".
- Mass is the quantity of matter contained in a substance.
- In chemical reactions, the mass of reactants must always be the same with the mass of the product baring any loss.
- In an isolated system, there is no exchange of energy and mass.
- Chemical systems are usually treated as isolated systems in which mass is conserved.
Learn more:
Chemical laws brainly.com/question/5896850
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