Question

(1)从（ ）到（ ）任意一点的线段叫半径．

Answer 1

星空流雨R,

(1)从（圆心）到（圆上）任意一点的线段叫半径．

(2)通过（圆心）并且（两端）都在（圆上）的线段叫做直径．