To solve this exercise it is necessary to use the concepts related to Difference in Phase.
The Difference in phase is given by

Where
Horizontal distance between two points
Wavelength
From our values we have,


The horizontal distance between this two points would be given for

Therefore using the equation we have




Therefore the correct answer is C.
Answer:
Power = 70 W
Explanation:
Given that,
Force, F = 70 N
Height, h = 5 m
Time, t = 5 s
We need to find the power of the object. We know that,
Power = work done/time
Put all the values,

So, the required power is 70 W.
(D)
Explanation:
The more massive an object is, the greater is the curvature that they produce on the space-time around it.
Answer
10
Explanation:
goes up by 10 each time 10 to 20 to 30