Knowledge Check Question 17 A circle with center $H$ is shown in the figure below. (a) Name a radius: (b) Name a diameter: (c) Name a chord: (d) If the length of $\overline{H G}$ is 2 units, what is the length of $\overline{I J}$ ? Megan E

Step 1 ：(a) A radius of the circle could be \(\overline{HG}\), \(\overline{HI}\), or \(\overline{HJ}\).

Step 2 ：(b) A diameter of the circle could be \(\overline{GJ}\), \(\overline{GI}\), or \(\overline{IJ}\).

Step 3 ：(c) A chord of the circle could be \(\overline{GJ}\), \(\overline{GI}\), or \(\overline{IJ}\).

Step 4 ：(d) Since the length of \(\overline{HG}\) is 2 units and \(\overline{HG}\) is a radius of the circle, the length of \(\overline{IJ}\), which is a diameter of the circle, is twice the length of the radius. Therefore, the length of \(\overline{IJ}\) is \(\boxed{4}\) units.