Explique el método que utiliza a las cefeidas para determinar la edad del Universo.

The original term of was descriptive of lower-class people who performed manual labor.

Compare the lives of slaves in mines and farms versus those in households

Analyze the quotation below in the context of european exploration in the americas. as you read the quote, think about what it says about columbus's motivations to explore. was he interested in gaining knowledge, wealth, or both? how did his motivations influence how he treated the people already living in the americas? i did not try to examine them in detail, because it could not be done in 50 years. for my desire is to see and discover as much as i can before returning to your highnesses, our lord willing, in april. it is true that in the event of finding places where there is gold or spices in quantity i should stop until i had collected as much as i could. i, therefore, proceed in the hope of coming across such places.