Answer:
1 - a/variable
2 - d/statistic
3 - b/population
4 - c/data
5 - e/parameter
6 - f/sample
I did comment asking if the two you'd already selected were definitely correct, but no answer was given, so I apologise if this is wrong. This is what I would put.
ANSWER
D. 25 feet
EXPLANATION
The height of the wall,h, the taut wire and the distance from the base of the pole to the point on the ground, formed a right triangle.
According to the Pythagoras Theorem, the sum of the length of the squares of the two shorter legs equals the square of the hypotenuse.
Let the hypotenuse ( the length of the ) taught wire be,l.
Then




