When driving on a highway outside a town it turned out that your car cannot reach a minimum speed of 80 km/h on a hill (e.g. because of insufficient output of its engine or weight of the transported load). May you continue driving on the highway?
Yes. It is important that the vehicle reaches this speed on a flat ground.
No. You are obligated to leave the highway at the nearest exit.
No. You are obligated to park the vehicle on a shoulder and mark it as a traffic obstacle.