Answer:
longitudinal research
Explanation:
Longitudinal research is a type of research that involves repeated observation of same variables over a long period of time which may be weeks, months and even years. It can be used to draw correlation between variables that do not have several related background variables.
<u>Answer:</u>
Approximate longitude of mainland Africa's westernmost point is 17° 31' 50.2" W.
<u>Explanation:</u>
This point of the longtitude is considered as the section of the city Dakar in the country Senegal.
Dakar is an incredible and historic metropolitan city and also known as the capital of Senegal. It is one of the biggest harbours in West Africa and a city renowned as a venue for the performances of the Paris-Dakar Rally. However, vast airport is also instituted near the city, which receives travellers from each and every corner world.
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Answer:
Copper:
Copper compounds produce blue colors in fireworks. Although Copper has a red appearance in solid form, when it’s set alight it creates stunning blue fireworks. Copper is used in electrical wire and roughly half of all copper mined is used for this purpose.
Darius of Persia maintained control over his empire by the use of provincial governors known as satraps. These satraps ruled areas that were larger than most kingdoms throughout the world, giving them tremendous power and wealth over their division of the empire. Satraps had a number of responsibilities, most notably needing to pay an annual tribute to the emperor and raising soldiers from their province during a time of war. By delegating authority to satraps, Darius was able to make decisions that affected all his empire rather than one region, and whenever he needed a military force (such as during the Persian wars with Greece), he could mobilize the largest army on Earth.
