For the following questions, use the parameter values a=18, b=1,y=0.01,D=50,pf=1,w=47, and v=0.01. i. ii. Suppose that a forester is only interested in the timber value of theforested land. Using t Excel, find the foesters optimal rotation length T. Do this for different distances away from the coast (i.e for x=(0,1,2,. . .,15). How does the optimal rotation length change as the distance from the coast x changes? Explain. Plot the NPV of th/. e land dedicated to forestry as a function of x and include it in the graph you created in part a ii. Make sure you explain how you found the answer. Supoose that the society values both timber and non-timber values. How does the oprimal rotational length and the NPV of the forested land for socirty compare to the forester's optimal rotation length and NPV of forested land? Similar to the abovem find the society's optimal rotational length T for the different distances from the coast using Excel. Plot the society's NPV of the land devoted to forestry as a function of x and include it in the graph you created in b ii. Make sure you explain how you found your