Assume you have created a mechanical arm that can hold a pen. The arm can perform the following tasks:

• Lower the pen to a piece of paper.
• Raise the pen from the paper.
• Move the pen 1 inch along a straight line. (If the pen is lowered, this action draws a 1-inch line from left to right; if the pen is raised, this action just repositions the pen 1 inch to the right.)
• Turn 90 degrees to the right.
• Draw a circle that is 1 inch in diameter.

Draw a flowchart or write structured pseudocode describing the logic that would cause the arm to draw or write the following. Have a fellow student act as the mechanical arm and carry out your instructions. Don’t reveal the desired outcome to your partner until the exercise is complete.

a. A 1-inch square

b. A 2-inch by 1-inch rectangle

c. A string of three beads

d. A short word (for example, cat)

e. A four-digit number