The amount of concrete, c, needed to make a walkway around a circular swimming pool varies directly as the square of the diameter, d, of the pool. Which statement is true?
OA If the diameter of the pool is doubled, the amount of concrete needed is multiplied by 2.
•B. If the diameter of the pool is doubled, the amount of concrete needed is multiplied by 4.
OC. If the diameter of the pool is halved, the amount of concrete needed is multiplied by 2.
OD. If the diameter of the pool is halved, the amount of concrete needed is multiplied by 4.

B.

For plato users

B.   If the diameter of the pool is doubled, the amount of concrete needed is multiplied by 4.

Step-by-step explanation:

I just  took the test and had 100 .

Step-by-step explanation:

For all Plato users

step-by-step explanation:

points a and b are equidistant from the desired line, so the line you find by using them will go through point r.

using points other than a and b will give the desired line only if they are equidistant from r. if they are randomly located, the perpendicular line you create will not necessarily go through point r, hence will not be a solution to the problem.