The brownish rock is a sedimentry rock was formed when things like sand, mud, or pebbles get laid down in layers. Eventually the layers are lithified.
The grey rock is a metamorphic rock and was when other rocks are changed because of heat or pressure. Earth movements can cause rocks to be deeply buried or squeezed. As a result, the rocks are heated and put under great pressure. They do not melt, but the minerals they contain are changed chemically, forming metamorphic rocks.
The red dots rock is an igneous rock. Igneous rock forms when hot, molten rock crystallizes and solidifies.
I believe the answer to your question would be Fluorine. I hope I answered your question, my friend. :)
Explanation:
The aggregation of methods used in order to accomplish a goal is called technology.
Whether technology is used to accomplish a goal which society does not deem acceptable then the goal is bad. The same technology can be used to do good. So, the question whether technology is harmful or useful depends on the goal a person wasts to acheive.
Let us take an example
The internet is one of the greatest discoveries of mankind which allows people access to unlimited information. It can be used for a variety of different services such buying goods and services. However, the internet is also a technology that facilitates illegal activities that circumvents government intervention. This way of technology being used is harmful.
Answer:
249.94ppm
Explanation:
Given parameters:
Mass of Pb(NO₃)₂ = 0.025g
Mass of water = 100g
Unknown:
Concentration of solution in ppm = ?
Solution:
Concentration in parts per million gives the amount of solute found in a million units of the solution. They are desirable for expressing very small amount of solutes in a large solution. For example, the level of arsenic in the soil.
Concentration in ppm = 
A solution is made up of solute and solvent. The solvent here is water.
mass of solution = mass of solute + mass of solvent = 0.025 + 100 = 100.025g
Concentration in ppm = 
= 249.94ppm
