Over what period of time the cost of various types of intangible assets should be amortized by

Question:

Over what period of time the cost of various types of should be amortized by regular charges against revenue? (Your answer should be in the form of a principle or guideline rather than a specific number of years.) What method of amortization is generally used?
Intangible Assets
An intangible asset is a resource controlled by an entity without physical substance. Unlike other assets, an intangible asset has no physical existence and you cannot touch it.Types of Intangible Assets and ExamplesSome examples are patented...