The north atlantic treaty organization (nato)
was formed in 1949 primarily to
(1) provide for the mutual defense of the
member nations
(2) promote social and cultural exchanges
between members
(3) promote free trade between the united
states and asia
(4) rebuild western europe’s war-ravaged
economy

la respuesta es si te gusta hacer lo que siempre haces cuando nunca ves a alguien en el espejo porque sabes que no siempre están ahí.

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.