Step 1:

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A pilot wanting to travel northeast.

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Wind is blowing from the west.

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Therefore, direction of wind speed is towards east.

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Triangle law of vectors addition:

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If the two vectors represented by the two adjacent sides of triangle, then the third side of the triangle determines the addition of the two vectors as shown.

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\"\"

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Wind speed is towards east direction.

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The airplane should move in the north-east direction.

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If the airspeed is moving in north direction, then the resultant component of north and east gives northeast direction.

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Hence the airspeed should direct in north direction so that airplane moves in the north-east direction.

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Therefore, airspeed is in north direction.

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Solution:

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First option is correct.

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2) \ \ Airspeed of airplane is \"\" kmph.

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Wind is blowing from the coast out to sea at \"\" kmph.

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Wind is blowing from the coast out to sea means that it opposes the air speed.

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Therefore, resultant relative speed of airplane is \"\" kmph.  

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Airplane is \"\" km off the coast above the sea. 

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Distance traveled by the plane to reach the shore is \"\" km. 

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\"\".  

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\"\"  

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\"\" 

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Substitute \"\" km and \"\" kmph in the expression.

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\"\" hr. \ \  

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\"\". 

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Therefore, time taken by the plane to reach the shore is \"\". 

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Solution: 

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Option (c) is correct.