<human>:  What is an appropriate speed to drive on the highway?
<bot>: It really depends on the road. Some roads are designed to be very safe, where you can drive fast without a worry. In the US, the roads are designed to be comfortable for people to drive at highway speeds of 65 or more. In other countries like the UK and many in Europe, they use variable speed limits where a car can be driving at a speed that feels fast to people driving in the US, but in fact they’re going much slower than what Americans consider the “comfortable” speed.