Answer:
C.
Explanation:
We can use the distance formula to find the distance between the center of circle Q and point R, which is also the radius of the circle. Then, we can multiply this value by 2 to get the diameter of the circle.
Distance Formula:
The distance between two points with coordinates (x1, y1) and (x2, y2) is given by the formula:
d = sqrt((x2 - x1)^2 + (y2 - y1)^2)
Using the distance formula, we can find the radius of circle Q:
radius = sqrt((7 - 3)^2 + (1 - (-2))^2)
= sqrt(4^2 + 3^2)
= 5
Therefore, the diameter of the circle is:
diameter = 2 * radius
= 2 * 5
= 10
So, the length of the diameter of circle Q is 10 units.