Two perpendicular highways are going East and North from the point O considered kilometer 0. At kilometer 90 on the highway going East, a car takes the exit and goes South at 50 km/h. At the same moment, at kilometer 110 on the highway going North, a car takes the exit and goes West at 60 km/h. Find how fast (in km/h) is the distance between these cars changes at this moment. dD dt (km/h) Notes: 1. The answer must be entered as a decimal number. Example: 3.47 2. Do not enter the unit of measurement. 3. Round the answer to two decimal places, 4. The tolerance is 5%