Natasha and reanna observe a large airplane in the troposphere. Which experimental setup below would best determine how changing wind speeds might affect the airplane’s flight time to its destination?.

The correct answer is b, social stratification is needed for a society to exist. marxist theory regarding social stratification is that due to the differing economic capacities among people in society, a natural separation occurs between those that own the means of production and those that sell their labour in the production chain. 

Frequency is the number of complete oscillations of a wave per second.

That’s really nice!