Answer:
Well I know that when the liquid changes from clear to dark blue and small bubbles form and rise to the surface that is a reaction
Explanation:
Answer: Option (C) is the correct answer.
Explanation:
When chemical composition of a substance is not changing in a chemical reaction then it is known as a physical change.
For example, when water change state, from ice to steam then it means solid state is changing into gaseous state.
Therefore, it is a physical change.
And, a reaction which causes change in chemical composition is known as a chemical change.
For example, 
Thus, we can conclude that we can see water change state, from ice to steam. This is a physical change in matter.
Question 2: Answer is (B), Soil Conservation Act (1936)
Hope that helps!!!
Answer:
D.Geologists use data from three or more data stations to determine the location of the epicenter.
For example, copper is used for electrical<span> wiring because it is a </span>good conductor of electricity<span>. </span>Metal<span> particles are held together by strong metallic bonds, which is why they have high melting and boiling points. The free electrons in </span>metals<span> can move through the </span>metal<span>, allowing </span>metals<span> to conduct </span>electricity<span>.</span>