To calculate the size of the central angle of sector B in the pie chart, we can use the following fact:

A full circle has 360 degrees, and sector B is the remaining part of the pie chart after the 140° sector.

1. Subtract the angle of the given sector (140°) from 360°: $360^\circ - 140^\circ = 220^\circ$

So, the central angle of sector B is 220°.

Would you like more details or have any further questions?

Here are some related questions:

1. How would you calculate the percentage of the pie chart for sector B?
2. What is the significance of central angles in pie charts?
3. How could this concept apply to dividing any circle into specific angles?
4. How can you find the area of a sector if the radius of the circle is given?
5. What is the total number of degrees in any closed shape like a polygon?

Tip: Always remember that the sum of the angles in a circle is 360°, which is useful for calculating missing angles in sectors.