Trips Logistics, a third$-$party logistics firm that provides warehousing and other logistics services, is facing a decision regarding the amount of space to lease for the upcoming three$-$year period. $1,000$ square feet of warehouse space is required for every $1,000$ units of demand, and the current demand at Trips Logistics is for $100,000$ units per year. The manager forecasts that from one year to the next, demand may go up $25$ percent with a probability of $0\mathrm{.}5$ or go down by $25$ percent by a probability of $0\mathrm{.}5.$ The probabilities of the two outcomes are independent.