The answer is C: irrigation
The main differences are that in a Closed System there are a limited number of nutrients, whereas in an Open System of growth there are an unlimited amount of nutrients. ... In contrast, in a Closed System Growth, dead cells remain in the same area where living cells are attempting to divide.
When caused by humans, acid rain is most commonly a byproduct of intense air pollution. As pollutants are pumped into the atmosphere, the particles rise up to the point where water can condense around them thereby forming water vapor and rain drops; however, those rain drops are closely intertwined with the pollutants thereby giving them an acidic nature.
Answer: Kerogen
Explanation: a Kerogen is an organic substances that helps to permeate (has pores which allow the inflow and outflow of certain substances like air or watee)oil shells, Kerogen has not net been converted to oil.Kerogens are waxy in nature with complex structures,Kerogens can not be extracted using organic Kerogens also contain Sulfur and Nitrogen. Kerogen contains Hydrocarbons in the form of paraffin which disolves under high temperatures and pressure into substances similar to petroleum.
The definition of a free trade is the international trade left to its natural course without tariffs, quotas, or other restrictions. Which means that if there are no restrictions in the imports and exports more countries would be able to import or export different types of goods all over the world.
