Ok guys thanks for answering my other question, But I have another one. Which compositional layer is divided between three mechanical layers?

LayerDepth

Lithosphere0-100 km

Asthenosphere100-350 km Soft plastic *note: The mantle is not liquid!

Mesosphere350-2900km stiff plastic

Outer Core5100-6370 km solid

Explanation:

l i t o s p h e r e 0 - 100 km

a s t h e n o s p h e r e. 100 - 350 km

m e s o s p h e r e. 350 - 2900 km

o u t e r. c o r e. 5100 - 6370 km

I don't know if this helped at all but I hope it did!

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.

answer: enthalpy

explanation:

for a exothermic reaction, the energy is released i.e. the energy of the products is lower than the energy of the reactants.

= enthaply

= energy of products

= energy of reactants

as , thus comes out to be negative. negative value of enthalpy shows that the reaction is exothermic.