Stairs vs. Elevator Each firm in an office building occupies one floor of space, earns total revenue R = $380, and incurs a labor cost L = $300. Define h as the height (floor level) of the building. The intra-building travel cost is C s (h) = 10 h per floor for travel by stairs, compared to C s (h) = 27 + h for travel by elevator. 1) Illustrate the WTP for office space for the two travel modes for h = 1 to h = 53. What sort of firms use the stairs? 2) Suppose that as h increases beyond the third floor, the view improves, and workers are willing to accept lower wages. The saving in labor cost is $3 per floor. Draw the WTP curve for the building with elevators, including a value for h = 53