please dont solve if you are not 100% sure, i will downvote if answer is wrong A small business is considering buying an energy saving device which will reduce its consumption of fuel. The device will cost 32,000. Engineering estimates suggest that savings from using the device will occur at a rate of s(t) rupees per year, where s(t) = 20,000 e^-0.5t and t equals measured in years. Determine how long will it take for the firm to recover the cost of device.