Tom uses a computer program to draw a rectangle that is 2 inches wide and 4 inches long. He expands and shrinks the rectangle to create similar figures and records the length and width of each one. Tom graphs the length and width of each figure. He concludes that for all the rectangles, the side lengths of each figure have the same proportional relationship, and the ratio of length to width is the constant of proportionality.
Part A: What is the constant of proportionality?

Part B: Tom expands his rectangle to make a similar rectangle with a length of 14 inches. What is the width in inches?

49