What is the diameter of a circle? A. The distance around the circle. B. The distance from any point on the edge of a circle to any other point. C. The distance from the center to any point on the circle. D. The distance across a circle, through its center.

At the beginning of the year, adrian's savings account balance was \$28$28. each week, he deposits another \$15$15 into that account, and he doesn't spend any of his savings. is his savings account balance proportional to the number of weeks since the start of the year?