A.) The sentence which seems unrelated is #3 because it doesn't relate to how Native Americans could tell directions.
The paragraph:
Native Americans were able to hunt using various techniques. They could tell directions by examining where moss grew in the forest. Broken twigs and branches gave away where animals may have gone through. Lastly, keen ears could pick up the sounds of various mammals and birds.
B.) The sentence which seems unrelated is #2 because it doesn't have anything to do with investigations.
The paragraph:
Scientist's investigations have led to many discoveries. One of them includes cures to copious diseases. Additionally a scientist's patient investigations can lead to them uncovering many new and interesting facts about the Earth and the universe. To conclude, the results of any investigation can lead to many new and fascinating questions which can later be answered in further studies.
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