<u>Answer:</u> The correct answer is geographical map.
<u>Explanation:</u>
Model is defined as the three dimensional representation of a proposed structure in a smaller scale.
For the given options:
<u>Option 1:</u> PV = nRT
This is a proposed law. This law is known as ideal gas law. A law is defined as the rule which defined a correct procedure. For any gas behaving ideally, this law is used.
<u>Option 2:</u> Geographical map
Map is defined as the diagrammatic representation of an area of land or sea which also shows physical features, roads, cities etc..
A 3-D model can be prepared for geographical map.
<u>Option 3:</u> I believe that aliens exist
This is a hypothetical statement. It is a smart guess by the means of set of assumptions and observations. For its validation, we need to conduct some experiments.
Hence, the correct answer is geographical map.
Answer: 
kJ
Explanation:
The thermochemical equation for decomposition of ammonium nitrate is:
Given mass= 50.0 kg =
(1kg=1000g)
According to stoichiometry:
1 mole of 
gives = 82.1 kJ of heat
Thus 
of give =
kJ of heat
Thus kJ of heat is evolved from the decomposition of 50.0 kg of ammonium nitrate.
Answer:
w w w . g o o g l e . c o m
Explanation:
Rust on a rock that contains iron
Mineral absorbs water and changes into a new substance
