Ice is a mixture and it can be a compound at the same time. A mixture is when you have to substance's put together fro example you can mix salt and sugar together. But a compound is when two different elements or molecules are combined. Ice cream is a mixture or cream and sugar mainly.
Answer:
A) Sample B has more calcium carbonate molecules
Explanation:
M = Molar mass of calcium carbonate = 100.0869 g/mol
= Avogadro's number = 
For the 4.12 g sample
Moles of a substance is given by

Number of molecules is given by

For the 19.37 g sample

Number of molecules is given by


So, sample B has more calcium carbonate molecules.
The ratio of the elements of carbon, oxygen, calcium atoms, ions, has to be same in both the samples otherwise the samples cannot be considered as calcium carbonate. Same is applicable for impurities. If there are impurites then the sample cannot be considered as calcium carbonate.
Answer:
Increased use of resources
Additional waste produced
More construction
Cutting down trees
Answer:
If one astronaut used more force, then that one would be faster than the other. The independent variable is force. The dependent variable is speed.
Explanation:
Force is what is to be changed. Speed is what is being measured.
IV = Changed/factor DV=Measured/Changes by factor
For this question the answer is c