ne for sound installation and the other for electric cars. Could you calculate NPV and advise the owner on the best option? $10$ decibels costs $$500,$ option $1$ needs $40$ decibels of sound wall insulation and option $2$ needs $50$ decibels of electric cart Option $1$ initial investment of $10000$; with Value of life of $6$ years Option $2$ Extra fuel cost of $6000$; maintenance fees of $500$ in the first year; $550$ in the second year and $600$ in the third year. Scrap Value $950$ Discount rate $6\%$