Xiao Wei takes a bus to Huian, passing a crossroads. He saw the traffic warning sign as shown in the figure, in which the circular sign means _ _ _ _ _ _ _ _ _ _ _ _, which does not violate the traffi

Xiao Wei takes a bus to Huian, passing a crossroads. He saw the traffic warning sign as shown in the figure, in which the circular sign means _ _ _ _ _ _ _ _ _ _ _ _, which does not violate the traffic rules. (1) 50 on the circular sign indicates that the maximum speed of the car cannot exceed 50km/h;

(2) "Huian 25km" means that there is still 25km from here to Huian.

∫v = ST，

∴ The shortest time for a driver to arrive in Hui 'an on the premise of observing traffic rules:

t=sv=25km50km/h=0.5h。

So the answer is: the maximum speed of a car cannot exceed 50 km/h; 0.5.