1.an extention line indicates the limit of a dimension line.

2.a visible line is used to show invisible edges or contours of an object.

3.a center line is used to show the centers of holes of circular object.

4.break lines are used to show that part of the object has been added to the object.

5.leader lines are used to direct descriptive major information, notes,or special dimensions to features on the drawing and done mechanically.

true or false ​