Answer: b
Explanation: Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock
Answer:
The answer is Option 2: Earth rotates on its axis.
Explanation:
Polaris is also more commonly know as the North Star is a triple star system and it appears to us here on Earth as the brightest star in the Ursa Minor constellation. Because the North Star is almost directly in line with the rotational axis of the earth, which is the North Pole, the star appears to stand still in the sky while the other stars in the northern hemisphere seem to rotate around Polaris. It has been used by navigators to help guide them to their destinations when there was no other landmarks to gain a sense of cardinal direction.
Answer:
Option (B)
Explanation:
Tides refer to the subsequent rise and fall of the sea level which is caused due to the gravitational force of attraction between the earth and the moon.
The high tide refers to the rising up of sea level, and it very much helpful for navigation purposes. A ship can easily sail into the nearest harbor when there occurs a high tide, thereby helping the sailor to reach the nearest land touching place. This is commonly used by the ship sailors.
Thus, Mohammed should have the knowledge of tides, and how both high and low tides are useful for navigation.
Hence, the correct answer is option (B).
Answer:
its a. population stability