Observations are used to record the results of an experiment.
Answer:
Distance, d = 99990 meters
Explanation:
It is given that,
Speed of the train, v = 200 km/h = 55.55 m/s
Time taken, t = 1800 s
Let d is the distance covered by the train. We know that the speed of an object is given by total distance covered divided by total time taken. Mathematically, it is given by :



d = 99990 m
So, the distance covered by the train is 99990 meters. Hence, this is the required solution.
1. Li3N lithium nitride
AND
3.SO2 sulfur dioxide
Answer:
The wavelength of the radio wave will be 3.271 m
Explanation:
We have given frequency of the radio signal 
Speed of the light 
We have to find the wavelength of the radio signal
We know that wavelength is given by 
So the wavelength of the radio wave will be 3.271 m