Answer
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Hint: Ursa Major is a constellation which consists of a large number of stars in the northern sky. It is primarily known for having seven of its main stars. These stars form a structure-like ladle. Between the seven stars, the two stars, Dubhe and Merak, may be the Pole Star used for navigating.
Complete solution:
Locate and observe the constellation of Ursa Major first. The following seven stars can be found there: Dubhe, Merak, Phecda, Megrez, Alioth, Mizar and Alkaid. As shown in the figure, all these stars appear to form a spoon/ladle like shape.
The first three are on the imaginary ladle handle, and the remaining four are on the imaginary ladle bowl.
On the right side of the quadrilateral, consider the last two stars, Dubhe and Merak. Just imagine a line that passes through these two stars. Extend this line, from Merak to Dubhe, in an upward direction. A star is going to coincide with that extended line of imagination, a faint star. Your Pole Star will be this star.
With the help of Ursa Major, the Pole Star can therefore be located by extending the line that joins the two stars, Dubhe and Merak.
Using Ursa Major, the pole star can be located by extending an imaginary line from the last two stars towards the north.
In the north direction an imaginary line is drawn. Hence, option A is correct.
Note:
Keep the main seven Ursa major stars mentioned above and in the diagram in mind. Remember to look for the quadrilateral that has the stars Megrez, Phecda, Merak and Dubhe, and not the stars on the handle, while looking for the last two stars. Before extending it the imaginary line should only have two stars, Dubhe and Merak.
Complete solution:
Locate and observe the constellation of Ursa Major first. The following seven stars can be found there: Dubhe, Merak, Phecda, Megrez, Alioth, Mizar and Alkaid. As shown in the figure, all these stars appear to form a spoon/ladle like shape.
The first three are on the imaginary ladle handle, and the remaining four are on the imaginary ladle bowl.
On the right side of the quadrilateral, consider the last two stars, Dubhe and Merak. Just imagine a line that passes through these two stars. Extend this line, from Merak to Dubhe, in an upward direction. A star is going to coincide with that extended line of imagination, a faint star. Your Pole Star will be this star.
With the help of Ursa Major, the Pole Star can therefore be located by extending the line that joins the two stars, Dubhe and Merak.
Using Ursa Major, the pole star can be located by extending an imaginary line from the last two stars towards the north.
In the north direction an imaginary line is drawn. Hence, option A is correct.
Note:
Keep the main seven Ursa major stars mentioned above and in the diagram in mind. Remember to look for the quadrilateral that has the stars Megrez, Phecda, Merak and Dubhe, and not the stars on the handle, while looking for the last two stars. Before extending it the imaginary line should only have two stars, Dubhe and Merak.