__ | 21. | Chord | | A. | Distance all the way around a circle |

__ | 22. | Circumference | | B. | Distance from the middle of a circle to circle |

__ | 23. | Congruent | | C. | Distance across a circle, going through the center |

__ | 24. | Diameter | | D. | A flat, 2-d surface |

__ | 25. | Pi | | E. | Ratio between the circumference and the diameter |

__ | 26. | Plane | | F. | A line that touches a circle, but doesn't go through |

__ | 27. | Radius | | G. | A line going through a circle |

__ | 28. | Secant | | H. | An angular point |

__ | 29. | Tangent | | I. | The same shape |

__ | 30. | Vertex | | J. | a line inside of a circle whose endpoints are on the circle |