An ancient chinese candle clock tells the amount of time that has passed by the amount of wax that has been melted off the candle. each candle is divided into 12 sections, marked 1 inch apart. it takes 4 hours for each candle to completely melt, after which a new candle is lit. if two candles have completely melted and one candle has melted 4 in, how many minutes have passed since the first candle was lit?