I believe it’s 60km/h
I divided the total distance (120 km) by the time it took to get there (2h) to get this.
We will determine the wavelength through the relationship given by the distance between slits, this relationship is given under the function

Here,
m = Number of order bright fringe
= Wavelength
d = Distance between slits
Both distance are the same, then



Rearranging to find the second wavelength




Therefore the wavelength of the light coming from the second monochromatic light source is 550.3nm
Answer: Gravitational potential energy changes.
Explanation: This is because depending on the amount of mass in an object that’s the amount of gravity pulling you down to the center of the earth
I need the points please don’t be mad
C