LINE:
LINE Specify first point: Start point.
Specify next point or [Undo]: Position the cursor and then enter distance.
Specify next point or [Undo]: Position the cursor and then enter distance.
CIRCLE:
Drawing a Circle by Specifying Center and
Diameter
1. Click Home > Draw > Circle > Center, Radius on the ribbon.
2. Select an arbitrary point in the graphics window to specify the center point:
3. Type a value as the radius and press ENTER.
ERASE:
Method 1
Select the Erase command first and then select the objects to be erased.
Press Enter Key and the objects selected will disappear.
Method 2
Select the object to be erased.
Press the Delete Key.

(i) Click View tab Palettes panel Command Line.
(ii) Find. Press Ctrl + 9.
(iii) At the Command prompt, enter COMMANDLINE or COMMANDLINEHIDE.
(iv) L. It can be used for making simple lines in the drawing.
(v) C. It is the command used for making a circle in AutoCAD.
(vi) PL. This command can be used to make a Polyline in your drawing.
(vii) REC. This command will make a rectangle in AutoCAD.

(a). Draw lines                             - Line tool
(b). Draw free hand drawing       - Free transform tool
(c). Erase what we have drawn  - Erase tool

1. WAV (Waveform Audio File Format)
2. MP3 (MPEG Layer-3 Format)
3. AVI (Audio/Video Interleave)
4. MPEG (Moving Picture Experts Group)
5. AIFF (Audio Interchange File Format)
6. Rich Text Format

(i) Flyout of polygon tool has star tool in it.
(ii) The tool's keyboard shortcut is (Y).

Using the view commands
(i) Choose View > Zoom In for magnifying to the next preset percentage.
(ii) Choose View > Zoom Out for reducing and retracting to the previous preset percentage.
(iii) Choose View > Actual Size for the document to be displayed at 100%.
(iv) Choose View > Fit page in Window for scaling the view size to match the monitor size.
(v) Choose View > Fit Spread in Window for displaying the targeted spread in the window.
(vi) Choose View > Entire Pasteboard for displaying the current page or spread and its surrounding pasteboard that ().revisible within the document window.