The town of Glenforest needs an additional supply of water from a river. The town engine s selected two plans for comparison. a. Gravity plan: Divert water from upstream and carry the water through s pipeline to the b. Pumping plan: Pump water from the river closer to the town. This plan is built in two town stages, the first stage installed initially and the second stage installed ten years after Assume a 10% painterest rate and a 30 year life with no salvage value. The cost of each alternative is as follows , Alt X Alt Y Initial investment Additional investment in the 10h year Operation & maintenance cost Power cost Gravity plan $2,800K S10K per year 1,400K $200K $25K per year S50K per year Determine the more economical plan based on Present worth method