Answer:
Astronomers used the cross-staff for measuring the angle between the directions of two stars. ... Ships' officers used it to measure the elevation angle of the noontime Sun above the horizon, which allowed them to estimate their latitude
Explanation:
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The type of region described is an economic region because many of the goals of the EU have to do with trade, jobs, and the economy.
Luzon straight is the Island that lies in between the south chin sea and the pacific Ocean
Answer:

The unit of electric current that is equal to the flow of one Coulomb per second.
Ampere or ‘amp’ is a unit of electric current denoted by A. It is named after the French Physicist and Mathematician Andre-Marie Ampere, who is considered as the ‘Father of Electrodynamics’.