The volume of rain that fells in the field is simply given by the area of the field, which is

multiplied by the height of rain that fell, which is

Therefore, the volume is

70 meters is your answer
Note that the beginning is the 30 meter mark, and the ending is the 100 meter mark. Subtract the beginning amount from the end:
100 - 30 = 70
The vehicle traveled 70 meters.
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I don't know I guess its the plate tectonics
There you go!
as it is unnecessary to find velocity, so use the equation with v
remember to take all directions downwards as it is more convenient to calculate
after substituting the values, you have to reject the negative answed as time must be+
:)