As BBC ztrrtv B 4 C w.a)z
The train’s average speed is 80km/h
B.
technically it would depend if the resistors were in series or parallel but B is the answer.
Decreasing the distance between two objects having a considerable mass would increase the attraction on gravitation. The reverse is true that if you separate or inrease the objects distance would substantially decrease their gravitational attraction. Most object in our planet is held by its gravitational force towards it's center.
The FREQUENCY of light remains unchanged once it leaves the source.
