a. The distance between B and a is SKM. A and B March from a and B respectively (B is in the front, a is in the back) a. B is SKM away from the two places. A and B March from a and B (B is in the front and a is in the back) respectively. When a overtakes B, a's journey is s a and B's journey is s B. what is the relationship among s, s a and S B?

a. The distance between B and a is SKM. A and B March from a and B respectively (B is in the front, a is in the back) a. B is SKM away from the two places. A and B March from a and B (B is in the front and a is in the back) respectively. When a overtakes B, a's journey is s a and B's journey is s B. what is the relationship among s, s a and S B?

S a = s B + S

The function problem is 100km apart. When a car goes from place a to place B, the time t (H) for the car to arrive at place B and the average speed V (km / h) of the car are calculated·
When the distance is 100km and a car goes from place a to place B, the function of the time t (H) for the car to reach place B and the average speed V (km / h) of the car is ()

t=100/h

The distance between station a and station B is 100km. A car drives from station a to station B at a speed of 40km / h. In addition, there are other cars departing from station B at the same time. Every 15 minutes, the speed is 20km / h. then the car from station a can see () cars from station B along the way

The distance between station a and station B is 100km, and a car drives from station a to station B at the speed of 40km / h, with the time of 100km
100/40=2.5h
The number of vehicles from station B within 2.5 hours is
2.5*60/15=10
Then the car from station a can see (10) cars from station B along the way

In an outing, Xiao Ming starts from a and goes to B by bicycle at the speed of V (km / h). It takes t (H). It is known that a and B are 6 km apart
(1) Find the analytic expression of T with respect to v;
(2) At 15:00, Xiao Ming starts from B to return to a along the same road. If Xiao Ming wants to return to a before 15:20, what is the average speed of his bicycle per hour?

（1）t=6/v
（2）v=6/t=6/（1/3)=18km/s