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The value of an automobile purchased in 2014 can be approximated by the function V(t) = 30(0.85), where t is the time, in years, from the date of purchase, and V(t) is the value, in thousands of dollars. (a) Evaluate and interpret V(4), including units. (b) Find an expression for V '(t), including units. (c) Evaluate and interpret V '(4), including units. (d) Use Vit), V '(t), and any other considerations you think are relevant to write a paragraph in support of or in opposition to the following statement: "From a monetary point of view, it is best to keep this vehicle as long as possible."