Apair of scientist proposes two different theories to explain the same set of observations. what best explains the values of these competing theories?

 the question like this is called assumptions, but the assumptions have to be proved by experiments and prove to be the best, but generally in science, theories might change from time to time, so in science, it is necessary to prove the hypothesis, not just by putting up the theories.  
hope this helps 

There are many examples of how latin influence has come to america and is here to stay. one for example is the banana. a fruit that was only grown in south america for years but then came to america in the early 1900s. it was propagandized as an exotic fruit from latin america during the first world war and took america by storm. now bananas are wildly used in the united states as one of the most popular fruits. another example is clothing. now more than ever ponchos, tribal prints from latin american latinos (such as mexico, peru, honduras, colombia, etc) are popularizing the colorful prints the latin american indigenous people would use, on back packs, sweaters, jewelry, blankets, etc in the "hipster movement." these things were originally popularized in the 90s after a mass movement of immigration after the regan administrations amnesty. but this trend continues in america today.

Mother mama gahahahaha