La diferencia es que uno ayda (empresario) para aydar al que inventa (inventor) ejemplo: un inventor nesecita ganancias para su invento pero el no sabe como asi que le dice a sus empresarios si lo ayudan para que esas ganancias suban y asi el inventor hace su innovacion
I would say that the resource you could use to find the meaning of <em>ambiguous </em>is the dictionary.
An almanac is an annual publication about weather, crops, etc.
A thesaurus is a dictionary of synonyms.
An encyclopedia is self-explanatory.
Well, since we are dealing with rocks, I'm just going to say that is is erosion
