The sales of a small company were $27,000 in its second year of operation and $63,000 in its fifth year. Let y represent sales in the xth year of operation. Assume that the data can be approximated by a straight line.

(a) Find the slope of the sales line, and give an equation for the line in the form y = mx + b.

(b) Use your answer from part (a) to find out how many years must pass before the sales surpass $100,000.