They allowed sailors to go on longer voyages plus they help navigators map the coastlines.
They brought back specimen samples
Answer:
hmm I don't know-how to explain
hoover
Glass-Steagall Act of 1932
Federal Home Loan Bank Act
Hawley-Smoot Tariff
The Stinson Doctrine
Federal Farm Board
not hoover
Fair Labour Standards Act
Federal Emergency Relief Act
Civilian Conservation Crops
Agricultural Adjustment Administration
Answer: In a group of city-states, each city-state is independent and rules by its own king. No central power controlled all of the city-states. In an empire, consisting of a nation and the city-states and nations it has conquered, one ruler is in control.
Explanation: One has a king in where the other has just a ruler