In this question, R starts by walking 1 km to the east. Then he turns south and walks 5 km. This means R is now 5 km south and 1 km east from his starting point.

Next, R turns to the east again and walks 2 km. This means he is now 5 km south and 3 km east from his starting point.

Finally, R turns north and walks 9 km. This means he is 4 km north and 3 km east from his starting point.

To find the distance between R and his starting point, we can use the Pythagorean theorem, which states that in a right-angled triangle, the square of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the other two sides. In this case, the distance between R and his starting point is the hypotenuse of a right-angled triangle, with the sides measuring 4 km and 3 km.

Using the Pythagorean theorem, we can calculate the distance as follows:

Distance^2 = (4 km)^2 + (3 km)^2

Distance^2 = 16 km^2 + 9 km^2

Distance^2 =