Charlotte is traveling 15 meters per second. which expression could be used to convert this speed to kilometers per hour? a (15 meters/1 second)(60 seconds/1 minute)(60 minutes/1 hour)(1000 meters/1 kilometer) b (15 meters/1 second)(1 minute/60 seconds)(1 hour/60 minutes)(1 kilometer/1000 meters) c (15 meters/1 second)(60 seconds/1 minute)(60 minutes/1 hour)(1 kilometer/1000 meters) d (15 meters/1 second)(1 minute/60 seconds)(60 minutes/1 hour)(1 kilometer/1000 meters)