Answer: Extraordinary assumption
Explanation: Appraisal could be defined as the estimation or evaluation of an object, property or structure in other to determine either the worth, condition or nature of such property or object. 
An Extraordinary assumption during appraisal means a presumption that certain unknown information exists or is a fact. It assumes a condition which is unknown to be true and as such if the information is found to be false may alter the result or conclusion of the appraisal. 
Such is the scenario above, when the appariser assumes there is no leakage or contamination based merely on unknown fact. 
 
        
             
        
        
        
Yes it does because natural resources play a crucial role in deciding the shape and size of development in a country. The western countries are highly developed mainly due to profusion of minerals, vegetation, natural fishing harbours etc. Plenty of oil inside the earth in the Middle East and South America is major factor in economic development of countries of these regions. Countries free from frequent visits of natural disasters are likely to be more developed than those who face the fury of disasters much time a year. Bangladesh and Philippines are a case in point. The countries that are always beset by monsoon, floods and landslides face tough hurdles in building infrastructure and carrying out development. Factors like proximity to high mountains, deserts and wild forests hamper pace of development to a great extent.
        
             
        
        
        
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