Which describes how early humans used wind and solar power for the same purpose?

to heat their homes in the winter months
to pump water from a river to another location
to grind grain into powder that could be used for other purposes
to provide relief from the heat during the summer

As a result of the work of the house un-american activities committee, hundreds of people were

Which act of the conquistador pizarro was crucial in overthrowing the inca? a. the destruction of the ancient inca city, machu picchu b. the siege of the inca capital near the cuzco valley c. the execution of the last inca ruler, atahualpa d. the unexpected deaths of 3 million inca warriors e. the murder of former inca emperor, huascar

Why did einstein write a letter to president roosevelt