PLZ HELP ASAP!!!!!!!,Boris is playing on the mall escalators. One escalator goes up, one goes down, and one is out of service; otherwise, they're all identical. The up and down escalators go at the same speed. You can assume that Boris always runs at the same speed.Boris can run up the up escalator in 6 seconds. He can run up the down escalator in 30 seconds. How long does it take him to run up the out-of-service escalator? Explain your answer