URGENT!!!

The manager of the company ABC (requiring warehouse) has two alternatives: i) rent from a spot market, ii) leasing company, for the three-year period planning horizon. It is forecasted that ABC will handle a demand of 20,000 items while each item needs 1sqft. The three-year lease costs $1,5 and the spot market rate is $2 per sq. ft per year. From one year to the next, demand may go up by 50 percent with a probability of 0.7 or go down by 20 percent with a probability of 0.3 . Similarly, from one year to the next, spot prices for warehouse space may go up by 25 percent with probability 0.5 or go down by 50 percent with probability 0.5 . The spot prices and demand fluctuate independently. The leasing contract is not flexible and provides 30.000 sq. ft space, if it is signed. ABC sells each product $3. Which alternative is more profitable? (Draw decision tree, use multiplicative binomial representation, discount factor =%10)(40 points )