Problem: Portuguese natives comprise a very small percentage of Guinea-Bissauans. After Guinea-Bissau gained independence, most of the Portuguese nationals left the country. The country has a tiny Chinese population. These include traders and merchants of mixed Portuguese and Chinese ancestry from Macau, a former Asian Portuguese colony.
What natives comprise a very small percentage of the population?
The answer is the following: Portuguese

Problem: South Slavic dialects historically formed a continuum. The turbulent history of the area, particularly due to expansion of the Ottoman Empire, resulted in a patchwork of dialectal and religious differences. Due to population migrations, Shtokavian became the most widespread in the western Balkans, intruding westwards into the area previously occupied by Chakavian and Kajkavian (which further blend into Slovenian in the northwest). Bosniaks, Croats and Serbs differ in religion and were historically often part of different cultural circles, although a large part of the nations have lived side by side under foreign overlords. During that period, the language was referred to under a variety of names, such as "Slavic", "Illyrian", or according to region, "Bosnian", "Serbian" and "Croatian", the latter often in combination with "Slavonian" or "Dalmatian".
What is one of the main causes of the turbulent history?
The answer is the following: expansion of the Ottoman Empire

Problem: For most of the Soviet Union's existence, it was commonly referred to as "Russia," even though technically "Russia" was only one republic within the larger unionalbeit by far the largest, most powerful and most highly developed.
What was the largest republic in the Soviet Union?
The answer is the following: Russia

Problem: The economic structure of the Empire was defined by its geopolitical structure. The Ottoman Empire stood between the West and the East, thus blocking the land route eastward and forcing Spanish and Portuguese navigators to set sail in search of a new route to the Orient. The Empire controlled the spice route that Marco Polo once used. When Vasco da Gama bypassed Ottoman controlled routes and established direct trade links with India in 1498, and Christopher Columbus first journeyed to the Bahamas in 1492, the Ottoman Empire was at its zenith.
When did Christopher Columbus sail to the Bahamas?
The answer is the following:
1492